As many of you know, I’m deeply involved in politics because democracy doesn’t protect itself. But being on political lists means my phone gets slammed with dozens of unsolicited fundraising texts every single day. Frankly, I don’t care about 98% of them. (with all due respect to Democratic congressional candidates in Nebraska and Kansas) Typing “STOP” by hand dozens of times a week is tedious and frustrating. So, like any software engineer, I built an Android app to automate the problem away: SMS Filter.

How It Works

SMS Filter quietly runs in the background on your Android phone. (Sorry, has to be Android) When a text, picture message, or RCS chat arrives from an unrecognized number, the app checks for standard opt-out keywords (like STOP, END, STOP to cancel, or STOP to quit), automatically fires back the required opt-out reply, and notifies you that it handled it.


Privacy was my number one design requirement:

  • Zero Cloud Syncing: The app runs 100% on your device. Your address book and messages are never copied, uploaded, or shared with third-party servers. Like me. I don’t even want all my contacts, let alone yours.
  • Smart Contact Protection: It checks your Google Contacts in real time, so messages from friends, family, and colleagues are never touched. It can also check HubSpot if you have it. Requires a Legacy App API Key.
  • Safety Controls: It includes a 24-hour per-sender cooldown to prevent automated reply loops, and it automatically protects group texts so it never broadcasts an accidental “STOP” to friends.

Help me Test It.


The app is feature-complete, thoroughly tested, and running via Google Play’s internal testing track. Now I need a few volunteers with Android phones to try it out and share feedback before a wider release.
If you’re tired of political spam and want early access, head over to the contact form at digiroth.com and drop me a note with the Gmail address you use for Google Play. I’ll send you an invite link right away!