A fun example is the slow loris attack. You send your requests character by character with 20+ seconds between packets. For mobile 20 seconds can happen so if the server doesn't use a running window to check timeouts it can't kill the connection.

Now you do this 1000 times you use barely any resources but the server uses 1GB in stack allocations which might be the maximum and noone else can connect.

https://en.wikipedia.org/wiki/Slowloris_(computer_security)