Frequent connection errors using API from phone
I have an application that sends information to the Zipabox via the API from my phone. It frequently (sometimes once an hour or more) generates errors like "android.system.ErrnoException: connect failed ENETUNREACH (Network is unreachable)", "java.net.SocketTimeoutException: Failed to connect to my.zipato.com/188.8.131.52 (port 443) after 15000ms" and "java.net.SocketTimeoutException: SSL handshake timed out".
I also send information from Google App Scripts, but they don't seem to have the same problem. Why would there be this difference? I've checked the times and it's not always when I'm on public transport with bad connections. Sometimes I'm asleep, sometimes I'm in the office... I can't see a pattern to it.