Clear Google Play Failed Download Space I recently tried installing an app that was around 1.8GB to my Nexus 7 (8GB). it's a device with unfortunately small internal storage, so I had about 2GB free before attempting the install. I come back later, the download has failed due to not enough storage space. no big surprise there. but now, my device only has 350MB free! strangely enough, the graph in storage settings appears as if it had that full 2GB or so free, but lists only 350MB.

how can I get my free storage space back from the failed download? my device is rooted, no root file browser or terminal, but I do have the Android SDK and tools.

another thing to note: my device is constantly complaining about its free space in the form of a notification. also, every app download from Google Play (even a tiny 2MB app) fails due to not enough storage space. for some reason, that always happens when my device goes under 500MB free. I don't understand it, but, it's 'normal'.
When we download big games (such as modern combat series), first play store download its additional files. Application/games additional files are saved on internal memory folder called "Android".  Inside of that folder, there's two directories. One is "data" other one is "obb". You can access that folder with any file manager app or by connecting your device to a PC (via USB or WIFI). (No need the root)

Search your app additional files in those folders and delete them. Most of the time additional files are saved with the app named folder. For an example "deadtrigger 2" game additional files saved folder called as "com.madfingergames.deadtrigger2".