But to shoot down other counties aircraft over Gaza would be to make the political statement that it is their airspace, which Is unacceptable

Gaza is not Israeli airspace.

Sleep as Android and Duolingo

The German Government, and it is an offline and encrypted app. Not everything governments do is bad.

The German Government, and it is an offline and encrypted app. Not everything governments do is bad.

SoGo

Drip is a good option. Funded by Mozilla and German Govt

Unless the data you hold is so sensitive that it cannot be stored in the cloud, I think a cloud approach is the way to go. That way you get predictable costs and reliable uptime