Pretty much every app I have has delayed notifications, and no matter of battery optimization settings can fix it.

Any service like Briar that wants to sit atop base smartphones will need to deal with this tension. A fallback is to poll intermittently for new messages, which when tuned correctly can indeed be fairly battery life forward. Of course then your messaging experience is lower bounded by your refresh interval. Modern smartphone OSes also will ruthlessly cut long-running connections in the face of power-save events on device.

In general I think an external radio that you connect your smartphone to via Bluetooth, like Meshcore or Meshtastic, is a better experience overall than simply using a smartphone. Dedicated radios keep smartphone batteries topped up, and having the option to setup an antenna means that if you happen to be in an area where permanent radio setup is plausible, you can lean on good site characteristics, antennas, and filters. It’s hard for a government to ban radios altogether and ISM-ish band devices have a variety of uses in pretty much any developing or developed country (often used in small things like meters or monitors.) And for folks who just some off-grid data capabilities, this approach offers high flexibility without the burden of licensing.

For folks considering going into this, I suggest joining Meshtastic or Amateur Radio communities. I find the further you get from amateur radio or networking communities (mesh* communities have a mix of folks and some can have pretty poor understanding of how radios work), the more the information becomes unreliable and more suffuse with political/social goals than matters like understanding signal propagation or congestion. If you’re in a developed country, Amazon likely has all you need to get started with the Mesh* world of LoRa UHF radios.

This is actually non-trivial. There's an app I was working on where I wanted to have a local first mode that allowed people to use the app for free without an account and there was also a cloud hosted version that allowed for team collaboration, etc.

For this kind of thing to work chunks of the app essentially need to be written twice. So, not fun.

Briar is a messenger app that worked on local networks, over Bluetooth, and over Tor if traveling the Internet. Fully encrypted and the purpose was decentralized, serverless messaging.

I liked the concept, and tested it out a little on my Android devices. But it looked straight out of 2009, and it had the issues described in the post. Still. Thanks for the work. I hope it can get revived or inspire others some day.

P.S. feature request! If Alice, Bob and Charlie are all contacts with each other, and Alice writes an offline message to Charlie, Alice should be able to opportunisticly hand the encrypted message to Bob on their shared network, and Bob can deliver it to Charlie.

The truth is donations do not work for tiny open source projects in the long term and even when Briar was quietly building for many years, it is clear that it is not enough.

If these are actually the problems, then why not throw 200 dollars of GPT 5.6 at these instead of shutting it down? Were these systematic problems (Apple/Google hegemony, for example) that couldn't be beat with code?