diff --git a/docs/development/plugin-creation.md b/docs/development/plugin-creation.md
index 2252be29f..78f3e0f9e 100644
--- a/docs/development/plugin-creation.md
+++ b/docs/development/plugin-creation.md
@@ -20,8 +20,8 @@ source "$PLUGIN_PATH/common/functions"
 case "$1" in
   hello)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG=$(get_running_image_tag $APP)
-    verify_app_name "$APP" "$TAG"
+    APP="$2"; IMAGE_TAG=$(get_running_image_tag $APP); IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+    verify_app_name "$APP"
 
     echo "Hello $APP"
     ;;
@@ -80,4 +80,4 @@ A few notes:
   dokku config:set --no-restart APP KEY1=VALUE1 [KEY2=VALUE2 ...]
   dokku config:unset --no-restart APP KEY1 [KEY2 ...]
   ```
-- As of 0.4.0, we allow image tagging and deployment of said tagged images. Therefore, hard-coding of `$IMAGE` as `dokku/$APP` is no longer sufficient. Instead, for non `pre/post-build-*` plugins, use `get_running_image_tag()` as sourced from common/functions.
+- As of 0.4.0, we allow image tagging and deployment of said tagged images. Therefore, hard-coding of `$IMAGE` as `dokku/$APP` is no longer sufficient. Instead, for non `pre/post-build-*` plugins, use `get_running_image_tag()` & `get_app_image_name()` as sourced from common/functions. See [pluginhooks](http://progrium.viewdocs.io/dokku/development/pluginhooks) doc for examples.
diff --git a/docs/development/pluginhooks.md b/docs/development/pluginhooks.md
index c6ec23a96..c74fb049a 100644
--- a/docs/development/pluginhooks.md
+++ b/docs/development/pluginhooks.md
@@ -244,7 +244,7 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 
 - Description: Allows you to run commands before environment variables are set for the release step of the deploy. Only applies to applications using buildpacks.
 - Invoked by: `dokku release`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -253,8 +253,8 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 dokku_log_info1" Installing GraphicsMagick..."
 
@@ -271,7 +271,7 @@ docker commit $ID $IMAGE > /dev/null
 
 - Description: Allows you to run commands after environment variables are set for the release step of the deploy. Only applies to applications using buildpacks.
 - Invoked by: `dokku release`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -280,8 +280,8 @@ docker commit $ID $IMAGE > /dev/null
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 dokku_log_info1" Installing $CONTAINER_PACKAGE..."
 
@@ -298,7 +298,7 @@ docker commit $ID $IMAGE > /dev/null
 
 - Description: Allows you to run commands before environment variables are set for the release step of the deploy. Only applies to applications using a dockerfile.
 - Invoked by: `dokku release`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -306,8 +306,8 @@ docker commit $ID $IMAGE > /dev/null
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 # TODO
 ```
@@ -316,7 +316,7 @@ verify_app_name "$APP" "$TAG"
 
 - Description: Allows you to run commands after environment variables are set for the release step of the deploy. Only applies to applications using a dockerfile.
 - Invoked by: `dokku release`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -324,8 +324,8 @@ verify_app_name "$APP" "$TAG"
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 # TODO
 ```
@@ -360,7 +360,7 @@ fi
 
 - Description: Allows the running of code before the container's process is started.
 - Invoked by: `dokku deploy`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -369,8 +369,8 @@ fi
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 dokku_log_info1 "Running gulp"
 id=$(docker run -d $IMAGE /bin/bash -c "cd /app && gulp default")
@@ -399,7 +399,7 @@ curl "http://httpstat.us/200"
 
 - Description: Can be used to run commands before an app is deleted.
 - Invoked by: `dokku apps:destroy`
-- Arguments: `$APP`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -409,9 +409,8 @@ curl "http://httpstat.us/200"
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
 
-APP="$1"; GULP_CACHE_DIR="$DOKKU_ROOT/$APP/gulp"
-TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; GULP_CACHE_DIR="$DOKKU_ROOT/$APP/gulp"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 if [[ -d $GULP_CACHE_DIR ]]; then
   docker run --rm -v "$GULP_CACHE_DIR:/gulp" "$IMAGE" find /gulp -depth -mindepth 1 -maxdepth 1 -exec rm -Rf {} \; || true
@@ -422,7 +421,7 @@ fi
 
 - Description: Can be used to run commands after an application is deleted.
 - Invoked by: `dokku apps:destroy`
-- Arguments: `$APP`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -456,7 +455,7 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 
 - Description:
 - Invoked by: `dokku deploy`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -464,8 +463,8 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 # TODO
 ```
@@ -474,7 +473,7 @@ verify_app_name "$APP" "$TAG"
 
 - Description:
 - Invoked by: `dokku run`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -482,8 +481,8 @@ verify_app_name "$APP" "$TAG"
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
-APP="$1"; TAG=$(get_running_image_tag $APP)
-verify_app_name "$APP" "$TAG"
+APP="$1"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+verify_app_name "$APP"
 
 # TODO
 ```
@@ -634,7 +633,7 @@ pluginhook receive-app $APP $newrev
 
 - Description: Allows you to run commands once a tag for an application image has been added
 - Invoked by: `dokku tag:add`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -642,18 +641,18 @@ pluginhook receive-app $APP $newrev
 # Upload an application image to docker hub
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
-APP="$1"; TAG="$2"; IMAGE="dokku/${APP}:${TAG}"
+APP="$1"; IMAGE_TAG="$2"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
 
 IMAGE_ID=$(docker inspect --format '{{ .Id }}' $IMAGE)
-docker tag -f $IMAGE_ID $DOCKER_HUB_USER/$APP:$TAG
-docker push $DOCKER_HUB_USER/$APP:$TAG
+docker tag -f $IMAGE_ID $DOCKER_HUB_USER/$APP:$IMAGE_TAG
+docker push $DOCKER_HUB_USER/$APP:$IMAGE_TAG
 ```
 
 ### `tag-remove`
 
 - Description: Allows you to run commands once a tag for an application image has been removed
 - Invoked by: `dokku tag:remove`
-- Arguments: `$APP $TAG`
+- Arguments: `$APP $IMAGE_TAG`
 - Example:
 
 ```shell
@@ -661,7 +660,7 @@ docker push $DOCKER_HUB_USER/$APP:$TAG
 # Remove an image tag from docker hub
 
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
-APP="$1"; TAG="$2"
+APP="$1"; IMAGE_TAG="$2"
 
 some code to remove a docker hub tag because it's not implemented in the CLI....
 ```
diff --git a/dokku b/dokku
index 7881fcf26..e054a5e61 100755
--- a/dokku
+++ b/dokku
@@ -51,7 +51,7 @@ fi
 
 case "$1" in
   receive)
-    APP="$2"; IMAGE_SOURCE_TYPE="$3"; TMP_WORK_DIR="$4"
+    APP="$2"; IMAGE=$(get_app_image_name $APP); IMAGE_SOURCE_TYPE="$3"; TMP_WORK_DIR="$4"
     dokku_log_info1 "Cleaning up..."
     dokku cleanup
     dokku_log_info1 "Building $APP from $IMAGE_SOURCE_TYPE..."
@@ -64,8 +64,9 @@ case "$1" in
 
   deploy)
     [[ -z $2 ]] && dokku_log_fail "Please specify an app to deploy"
-    APP="$2"; TAG="$3"; verify_app_name "$APP" "$TAG"
-    pluginhook pre-deploy $APP $TAG
+    APP="$2"; IMAGE_TAG="$3"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+    verify_app_name "$APP"
+    pluginhook pre-deploy $APP $IMAGE_TAG
 
     is_image_herokuish_based "$IMAGE" && DOKKU_HEROKUISH=true
     DOKKU_SCALE_FILE="$DOKKU_ROOT/$APP/DOKKU_SCALE"
@@ -85,10 +86,10 @@ case "$1" in
         DOKKU_PORT_FILE="$DOKKU_ROOT/$APP/PORT.$PROC_TYPE.$CONTAINER_INDEX"
 
         # start the app
-        DOCKER_ARGS=$(: | pluginhook docker-args $APP deploy $TAG)
+        DOCKER_ARGS=$(: | pluginhook docker-args $APP deploy $IMAGE_TAG)
         DOCKER_ARGS+=" -e DYNO=$PROC_TYPE "
         DOCKER_ARGS+=" -e DYNO_TYPE_NUMBER='$PROC_TYPE.$CONTAINER_INDEX' "
-        DOCKER_ARGS+=$(: | pluginhook docker-args-deploy $APP $TAG)
+        DOCKER_ARGS+=$(: | pluginhook docker-args-deploy $APP $IMAGE_TAG)
         BIND_EXTERNAL=$(pluginhook bind-external-ip $APP)
 
         [[ -n "$DOKKU_HEROKUISH" ]] && START_CMD="/start $PROC_TYPE"
diff --git a/plugins/00_dokku-standard/commands b/plugins/00_dokku-standard/commands
index fc0a42a3c..bd9864851 100755
--- a/plugins/00_dokku-standard/commands
+++ b/plugins/00_dokku-standard/commands
@@ -5,7 +5,7 @@ source "$PLUGIN_PATH/config/functions"
 
 case "$1" in
   build)
-    APP="$2"; IMAGE_SOURCE_TYPE="$3"; TMP_WORK_DIR="$4"
+    APP="$2"; IMAGE_SOURCE_TYPE="$3"; TMP_WORK_DIR="$4"; IMAGE=$(get_app_image_name $APP)
     verify_app_name "$APP"
 
     CACHE_DIR="$DOKKU_ROOT/$APP/cache"
@@ -60,16 +60,16 @@ case "$1" in
     ;;
 
   release)
-    APP="$2"; IMAGE_SOURCE_TYPE="$3"; TAG="$4"
-    verify_app_name "$APP" "$TAG"
+    APP="$2"; IMAGE_SOURCE_TYPE="$3"; IMAGE_TAG="$4"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+    verify_app_name "$APP"
 
     case "$IMAGE_SOURCE_TYPE" in
       herokuish)
         # *DEPRECATED* in v0.3.15: `pluginhook pre-release` will be removed in future releases
-        pluginhook pre-release "$APP" "$TAG"
+        pluginhook pre-release $APP $IMAGE_TAG
         # *DEPRECATED* in v0.3.22: `pluginhook pre-release-buildstep` will be removed in future releases
-        pluginhook pre-release-buildstep "$APP" "$TAG"
-        pluginhook pre-release-buildpack "$APP" "$TAG"
+        pluginhook pre-release-buildstep $APP $IMAGE_TAG
+        pluginhook pre-release-buildpack $APP $IMAGE_TAG
         if [[ -n $(config_export global) ]]; then
           id=$(config_export global | docker run -i -a stdin $IMAGE /bin/bash -c "mkdir -p /app/.profile.d && cat > /app/.profile.d/00-global-env.sh")
           test "$(docker wait $id)" -eq 0
@@ -81,15 +81,15 @@ case "$1" in
           docker commit $id $IMAGE > /dev/null
         fi
         # *DEPRECATED* in v0.3.15: `pluginhook post-release` will be removed in future releases
-        pluginhook post-release "$APP" "$TAG"
+        pluginhook post-release $APP $IMAGE_TAG
         # *DEPRECATED* in v0.3.22: `pluginhook post-release-buildstep` will be removed in future releases
-        pluginhook post-release-buildstep "$APP" "$TAG"
-        pluginhook post-release-buildpack "$APP" "$TAG"
+        pluginhook post-release-buildstep $APP $IMAGE_TAG
+        pluginhook post-release-buildpack $APP $IMAGE_TAG
         ;;
 
       dockerfile)
-        pluginhook pre-release-dockerfile "$APP" "$TAG"
-        pluginhook post-release-dockerfile "$APP" "$TAG"
+        pluginhook pre-release-dockerfile $APP $IMAGE_TAG
+        pluginhook post-release-dockerfile $APP $IMAGE_TAG
         ;;
 
       *)
@@ -170,13 +170,13 @@ case "$1" in
 
   run)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG=$(get_running_image_tag $APP)
-    verify_app_name "$APP" "$TAG"
+    APP="$2"; IMAGE_TAG=$(get_running_image_tag $APP); IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+    verify_app_name "$APP"
 
     shift 2
 
-    DOCKER_ARGS=$(: | pluginhook docker-args $APP run $TAG)
-    DOCKER_ARGS+=$(: | pluginhook docker-args-run $APP $TAG)
+    DOCKER_ARGS=$(: | pluginhook docker-args $APP run $IMAGE_TAG)
+    DOCKER_ARGS+=$(: | pluginhook docker-args-run $APP $IMAGE_TAG)
     [[ $DOKKU_RM_CONTAINER ]] && DOKKU_RUN_OPTS="--rm"
     has_tty && DOKKU_RUN_OPTS+=" -i -t"
     is_image_herokuish_based "$IMAGE" && EXEC_CMD="/exec"
diff --git a/plugins/apps/commands b/plugins/apps/commands
index 4924fb13b..f2e29666d 100755
--- a/plugins/apps/commands
+++ b/plugins/apps/commands
@@ -21,7 +21,8 @@ case "$1" in
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
     [[ "$2" == "tls" ]] && echo "Unable to destroy tls directory" && exit 1
     [[ "$3" == "force" ]] && DOKKU_APPS_FORCE_DELETE=1
-    APP="$2"; verify_app_name "$APP"
+    APP="$2"; IMAGE_TAG=$(get_running_image_tag $APP)
+    verify_app_name "$APP"
 
     if [[ -z "$DOKKU_APPS_FORCE_DELETE" ]]; then
       dokku_log_warn "WARNING: Potentially Destructive Action"
@@ -38,7 +39,7 @@ case "$1" in
 
     echo "Destroying $APP (including all add-ons)"
 
-    pluginhook pre-delete $APP
+    pluginhook pre-delete $APP $IMAGE_TAG
     DOKKU_APP_CIDS=$(get_app_container_ids $APP)
     if [[ -n $DOKKU_APP_CIDS ]]; then
       for ID in $DOKKU_APP_CIDS;do
@@ -47,7 +48,7 @@ case "$1" in
       done
     fi
 
-    pluginhook post-delete $APP
+    pluginhook post-delete $APP $IMAGE_TAG
     ;;
 
   help | apps:help)
diff --git a/plugins/apps/pre-delete b/plugins/apps/pre-delete
index c6f563d2c..49f3762bc 100755
--- a/plugins/apps/pre-delete
+++ b/plugins/apps/pre-delete
@@ -2,7 +2,7 @@
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$(dirname $0)/../common/functions"
 
-APP="$1"; CACHE_DIR="$DOKKU_ROOT/$APP/cache"
+APP="$1"; IMAGE_TAG="$2"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG); CACHE_DIR="$DOKKU_ROOT/$APP/cache"
 verify_app_name "$APP"
 
 if [[ -d $CACHE_DIR ]]; then
diff --git a/plugins/build-env/pre-build b/plugins/build-env/pre-build
index 900ee800f..98e9afd99 100755
--- a/plugins/build-env/pre-build
+++ b/plugins/build-env/pre-build
@@ -3,7 +3,7 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
 source "$PLUGIN_PATH/config/functions"
 
-APP="$1"; BUILD_ENV=""
+APP="$1"; IMAGE=$(get_app_image_name $APP); BUILD_ENV=""
 verify_app_name "$APP"
 
 [[ -f "$DOKKU_ROOT/BUILD_ENV" ]] && cat "$DOKKU_ROOT/BUILD_ENV" >> "$DOKKU_ROOT/ENV" && {
diff --git a/plugins/common/functions b/plugins/common/functions
index 7b0111c45..b3df13581 100755
--- a/plugins/common/functions
+++ b/plugins/common/functions
@@ -114,16 +114,10 @@ dokku_container_log_verbose_quiet() {
 }
 
 verify_app_name() {
-  local APP="$1"; local TAG="$2"
+  local APP="$1"
   [[ ! -n "$APP" ]] && dokku_log_fail "(verify_app_name) APP must not be null"
   [[ ! -d "$DOKKU_ROOT/$APP" ]] && dokku_log_fail "App $APP does not exist"
 
-  if [[ -n "$TAG" ]]; then
-    IMAGE="dokku/$APP:$TAG"
-  else
-    IMAGE="dokku/$APP"
-  fi
-  export IMAGE
   return 0
 }
 
@@ -136,12 +130,26 @@ verify_image() {
   fi
 }
 
+get_app_image_name(){
+  # return image identifier for a given app, tag tuple. validate if tag is presented
+  local APP="$1"; local IMAGE_TAG="$2"
+
+  if [[ -n "$IMAGE_TAG" ]]; then
+    IMAGE="dokku/$APP:$IMAGE_TAG"
+    verify_image "$IMAGE" || dokku_log_fail "app image ($IMAGE) not found"
+  else
+    IMAGE="dokku/$APP:latest"
+  fi
+  echo $IMAGE
+}
+
 get_running_image_tag() {
+  # retrieve current image tag for a given app. returns empty string if no deployed containers are found
   local APP="$1"
   [[ ! -n "$APP" ]] && dokku_log_fail "(get_running_image_tag) APP must not be null"
   verify_app_name "$APP"
 
-  CIDS=( $(get_container_ids $APP) )
+  CIDS=( $(get_app_container_ids $APP) )
   RUNNING_IMAGE_TAG=$(docker ps -a --no-trunc | egrep ${CIDS[0]} 2>/dev/null | awk '{ print $2 }' | awk -F: '{ print $2 }' || echo '')
   echo $RUNNING_IMAGE_TAG
 }
@@ -284,7 +292,8 @@ is_app_running() {
 }
 
 release_and_deploy() {
-  local APP="$1"; local TAG="$2"; verify_app_name "$APP" "$TAG"
+  local APP="$1"; local IMAGE_TAG="$2"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+  verify_app_name "$APP"
 
   if verify_image "$IMAGE"; then
     if is_image_herokuish_based "$IMAGE"; then
@@ -294,11 +303,11 @@ release_and_deploy() {
     fi
 
     dokku_log_info1 "Releasing $APP ($IMAGE)..."
-    dokku release "$APP" "$IMAGE_SOURCE_TYPE" "$TAG"
+    dokku release "$APP" "$IMAGE_SOURCE_TYPE" "$IMAGE_TAG"
     dokku_log_info1 "Deploying $APP ($IMAGE)..."
-    dokku deploy "$APP" "$TAG"
+    dokku deploy "$APP" "$IMAGE_TAG"
     dokku_log_info2 "Application deployed:"
-         dokku urls $APP | sed "s/^/       /"
+    dokku urls $APP | sed "s/^/       /"
     echo
   fi
 }
diff --git a/plugins/config/docker-args-deploy b/plugins/config/docker-args-deploy
index 9fee5b7c6..f63a2cb5b 100755
--- a/plugins/config/docker-args-deploy
+++ b/plugins/config/docker-args-deploy
@@ -3,9 +3,9 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_PATH/common/functions"
 source "$PLUGIN_PATH/config/functions"
 
-STDIN=$(cat); APP="$1"; TAG="$2"
+STDIN=$(cat); APP="$1"; IMAGE_TAG="$2"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
 DOCKERFILE_ENV_FILE="$DOKKU_ROOT/$APP/DOCKERFILE_ENV_FILE"
-verify_app_name "$APP" "$TAG"
+verify_app_name "$APP"
 
 if ! is_image_herokuish_based "$IMAGE"; then
   > "$DOCKERFILE_ENV_FILE"
diff --git a/plugins/enter/commands b/plugins/enter/commands
index 601895036..e78e4ba13 100755
--- a/plugins/enter/commands
+++ b/plugins/enter/commands
@@ -4,8 +4,8 @@ source "$(dirname "$0")/../common/functions"
 
 case "$1" in
   enter)
-    APP="$2"; TAG=$(get_running_image_tag $APP); CONTAINER_TYPE="$3"
-    verify_app_name "$APP" "$TAG"
+    APP="$2"; CONTAINER_TYPE="$3"; IMAGE_TAG=$(get_running_image_tag $APP); IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
+    verify_app_name "$APP"
 
     [[ ! -n "$3" ]] && dokku_log_fail "No container id specified"
 
diff --git a/plugins/ps/commands b/plugins/ps/commands
index 6f6210dd3..0acf81ac5 100755
--- a/plugins/ps/commands
+++ b/plugins/ps/commands
@@ -18,11 +18,13 @@ case "$1" in
 
   ps:start)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG=$(get_running_image_tag "$APP"); verify_app_name "$APP" "$TAG"
+    APP="$2"; IMAGE_TAG=$(get_running_image_tag $APP);
+    verify_app_name "$APP"
+
     ! (is_deployed $APP) && echo "App $APP has not been deployed" && exit 0
 
     if ! (is_app_running $APP); then
-      release_and_deploy "$APP" "$TAG"
+      release_and_deploy "$APP" "$IMAGE_TAG"
     else
       echo "App $APP already running"
     fi
@@ -30,7 +32,9 @@ case "$1" in
 
   ps:stop)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; verify_app_name "$APP"; DOKKU_APP_RUNNING_CONTAINER_IDS=$(get_app_running_container_ids $APP)
+    APP="$2"; DOKKU_APP_RUNNING_CONTAINER_IDS=$(get_app_running_container_ids $APP)
+    verify_app_name "$APP"
+
     ! (is_deployed $APP) && echo "App $APP has not been deployed" && exit 0
 
     if [[ -n "$DOKKU_APP_RUNNING_CONTAINER_IDS" ]]; then
@@ -60,10 +64,12 @@ case "$1" in
 
   ps:restart)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG=$(get_running_image_tag $APP); verify_app_name "$APP" "$TAG"
+    APP="$2"; IMAGE_TAG=$(get_running_image_tag $APP)
+    verify_app_name "$APP"
+
     ! (is_deployed $APP) && echo "App $APP has not been deployed" && exit 0
 
-    release_and_deploy "$APP" "$TAG"
+    release_and_deploy "$APP" "$IMAGE_TAG"
   ;;
 
   ps:restartall)
@@ -78,18 +84,19 @@ case "$1" in
 
   ps:scale)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG=$(get_running_image_tag "$APP"); verify_app_name "$APP" "$TAG"
+    APP="$2"; IMAGE_TAG=$(get_running_image_tag $APP)
+    verify_app_name "$APP"
 
     DOKKU_SCALE_FILE="$DOKKU_ROOT/$APP/DOKKU_SCALE"
     shift 2
 
-    generate_scale_file "$APP" "$TAG"
+    generate_scale_file "$APP" "$IMAGE_TAG"
     if [[ -z "$@" ]];then
       dokku_log_info1 "Scaling for $APP"
       dokku_log_info2 "$(< $DOKKU_SCALE_FILE)"
     else
       set_scale "$APP" "$@"
-      release_and_deploy "$APP" "$TAG"
+      release_and_deploy "$APP" "$IMAGE_TAG"
     fi
   ;;
 
diff --git a/plugins/ps/functions b/plugins/ps/functions
index f54f10101..f0e5aef78 100755
--- a/plugins/ps/functions
+++ b/plugins/ps/functions
@@ -11,8 +11,9 @@ print_dokku_scale_file(){
 }
 
 generate_scale_file() {
-  local APP="$1"; local TAG="$3"; local DOKKU_SCALE_FILE="$DOKKU_ROOT/$APP/DOKKU_SCALE"
-  verify_app_name "$APP" "$TAG"
+  local APP="$1"; local IMAGE_TAG="$3"; local IMAGE=$(get_app_image_name $APP $IMAGE_TAG); local DOKKU_SCALE_FILE="$DOKKU_ROOT/$APP/DOKKU_SCALE"
+  verify_app_name "$APP"
+
   copy_from_image "$IMAGE" "/app/DOKKU_SCALE" "$DOKKU_ROOT/$APP" 2>/dev/null || true
   if [[ ! -f $DOKKU_SCALE_FILE ]]; then
     dokku_log_info1_quiet "DOKKU_SCALE file not found in app image. Defaulting to a single web process"
diff --git a/plugins/tag/commands b/plugins/tag/commands
index 8bc308dd4..67d5496e4 100755
--- a/plugins/tag/commands
+++ b/plugins/tag/commands
@@ -1,32 +1,36 @@
 #!/usr/bin/env bash
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$(dirname $0)/../common/functions"
-source "$(dirname $0)/functions"
+
+tag_image() {
+  docker tag -f "$1" "$2"
+}
 
 case "$1" in
   tag:add)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG="$3"
+    APP="$2"; IMAGE_TAG="$3"
     verify_app_name "$APP"
     verify_image "$IMAGE" || dokku_log_fail "App image ($IMAGE) not found"
 
-    tag_image "$IMAGE:latest" "$IMAGE:$TAG"
-    dokku_log_info2_quiet "Added $TAG tag to $IMAGE"
-    pluginhook tag-add $APP $TAG
+    tag_image "$IMAGE:latest" "$IMAGE:$IMAGE_TAG"
+    dokku_log_info2_quiet "Added $IMAGE_TAG tag to $IMAGE"
+    pluginhook tag-add $APP $IMAGE_TAG
     ;;
 
   tag:deploy)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG="$3"
+    APP="$2"; IMAGE_TAG="$3"
     verify_app_name "$APP"
-    verify_image "$IMAGE:$TAG" || dokku_log_fail "App image ($IMAGE:$TAG) not found"
+    verify_image "$IMAGE:$IMAGE_TAG" || dokku_log_fail "App image ($IMAGE:$IMAGE_TAG) not found"
 
-    release_and_deploy $APP $TAG
+    release_and_deploy $APP $IMAGE_TAG
     ;;
 
   tag:list)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; verify_app_name "$APP"
+    APP="$2"
+    verify_app_name "$APP"
 
     dokku_log_info2_quiet "Image tags for $IMAGE"
     docker images "$IMAGE"
@@ -34,19 +38,19 @@ case "$1" in
 
   tag:rm)
     [[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
-    APP="$2"; TAG="$3"
+    APP="$2"; IMAGE_TAG="$3"
     verify_app_name "$2"
 
-    case "$TAG" in
+    case "$IMAGE_TAG" in
         latest)
-            dokku_log_fail "You can't remove internal dokku tag ($TAG) for $IMAGE"
+            dokku_log_fail "You can't remove internal dokku tag ($IMAGE_TAG) for $IMAGE"
             ;;
 
         *)
-            docker rmi "$IMAGE:$TAG"
+            docker rmi "$IMAGE:$IMAGE_TAG"
             ;;
     esac
-    pluginhook tag-remove $APP $TAG
+    pluginhook tag-remove $APP $IMAGE_TAG
     ;;
 
   help | tag:help)
diff --git a/plugins/tag/functions b/plugins/tag/functions
deleted file mode 100755
index 717eefb8c..000000000
--- a/plugins/tag/functions
+++ /dev/null
@@ -1,7 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
-source "$(dirname $0)/../common/functions"
-
-tag_image() {
-  docker tag -f "$1" "$2"
-}