[unicornporn]

Wire[1] is also an excellent option. Unlike Open Whisper Systems they wont hang you from a tree for building a third party app. Signal wont work without Gapps or Google Play Services on your Android phone and Google Chrome for desktop.

[1] https://wire.com/

[codethief]

Signal does work with MicroG (https://microg.org/), an open source reimplementation of Google Play Services.

[kuschku]

But that still requires using the Google Play Services library in the Signal APK, still doing analytics.

[tdkl]

I tried Wire after this WhatsApp news came out initially and brought about 10 people (friends/family) to it. They're satisfied how it works.