No they are (were) an actual native Android apps that install automatically without needing to go through Google play. They have a much tighter sandbox and restricted access to system APIs as a safety measure.
Simple, add additional columns for the frame of reference (e.g. Earth) and elevation. You could even store space coordinates using Sun as a reference point (though you would need to update data regularly for spacecraft as they move of course).
Why do you need to store the name of a country in the database? Frontend can take the country code and display a full name on its own, and do it in a localized way too.
North America has its own large oil reserves and AFAIK its countries mostly trade it with each other. Europe chooses to buy oil and gas from Russia, Saudis and other Asian countries because it's cheaper due to geographic proximity.
Linux has never been good at running old binaries. It's always assumed that you are running software compiled for the current version if your distribution, and programs that are not available can be compiled from source (because you obviously use only open source software). For everything else you need to use compatibility layers that provide necessary environment.
It works because the size of an array in main() function is known at compile time. Arrays in Rust have fixed size, at that size is part of their type. The type of the array you pass to from() is [i32; 5]
Been a long time since I used arch or it's derivatives, in what way is cachyos less stable?