Tiny computers aren't hard, we have PI's and a dozen alterantives. Efficiency and Power are the real issues.

Android and IOS have been doing power R&D for almost 20 years. When you stop using an android app, even for a short period, it saves a snapshot in memory and stops using it. The radio drivers are on their 20th revision and do everything in their power to save power. We're just starting off where they did prior to 2010. But we know how they solved the issues, we'll catch up. It's going to take time, we need to get everything working and stable first.

The signal problem is a lack of packages for arm-linux it is possible to build it i'm reading, but cross-compiling and keeping it up to date seems like a hassle.

My first thought was to try to find a smallish x86 tablet and carry a portable hotspot. But there's not a lot of those and power seems like it'll still be a problem.

I don't know that there are good solutions just yet, but we're not alone in wants. Hoping I can eventually craft something usefull or help contribute to someone who is.