No longer having my rooted Android slab and not yet willing to brick a new (WiFi only) Nexus 7 FHD, I was anxious to try this Grey Shirts NoRoot Firewall I had seen on several occasions when digging around in the Play Store. How good it is, is absolutely impressive. The feature set and granularity far exceeds those of the ones I played with, including avast! Mobile. Upon first run it'll build an APPS list of all installed networked Apps. PENDING ACCESS notifications will start presenting which you open to review connections to allow, block or build a rule. At first this is a bit tedious but unavoidable considering the level of connectivity of an Android device. Apps will turn red, yellow or green in the APPS list depending on the level of the rule(s). Those in white have not yet tried to connect and you can then either allow, block, build or just wait for a connect and examine the PENDING ACCESS notification. Running a newly installed App which attempts an immediate connection will present a PENDING ACCESS notification and if not will appear as white in the APPS list. Any App that attempts an access not meeting an existing rule(s) will present a PENDING ACCESS notification. This App needs: 1) Clear, sort, filter and save as txt or csv the ACCESS LOG. 2) Move up/down rules in App Detail. 3) Export/import rules. 4) Greater support of wildcards for domains rules, currently restricted to *. 5) One or two nit picky things I can't recall at the moment. I've posted up those as wishes in its Play Store reviews. I think Grey Shirts has a winner here for hard core Android geeks. The last update was on October 14 and according to their postings in Play Store, active development is ongoing. If they ever went to a paid model, my wallet is at the ready. FYI: NRFW does not work via a proxy (local or external) like some others but instead brilliantly uses Android's VpnService. -https://developer.android.com/reference/android/net/VpnService.html On first run, it prompts for a permission which you can accept and continue or deny and exit. Cheers.