wifi hotspot performance

Ok first I did search and didnt come up with anything to answer my questions so here goes. I just recently moved into a new apartment and have yet to have internet and cable hooked up, I am relegated to using either a T-Mobile hotspot device or Xfinity WIFI for internet, but both of them are slow and temperamental signals at best. I was wondering if there was anything I could do to my Nexus tablet and possible my Windows 7 laptop to try and increase the performance and try and get a more stable faster connection
If my post is in the wrong spot Admins please go ahead and move it