The Stop ICE Raids Alert Network let’s you send and receive mobile alerts about nearby ICE activity whenever, and wherever it occurs.
No downloadable app required. StopICE works with technology already built into your phone. Send and receive mobile alerts via text message, or at stopice.net from any mobile device with a tap of a button.
ICEBlock is very suspicious, no claims they make about privacy can be verified and Apple has access to all the userdata. As it is centrally run, there is also a good chance of the dev being threatened into handing over data to the feds.