I think if you don't want years of your life tied to a single provider you should try a pay as you go service when you consider buying a cell phone.
While these plans don't give you access to the latest models of phones for "free", but they do leave you with the flexibility to use as much time as you want and to set a budget, all while not get surprised come bill time.
Also, cell phone provider contracts are often filled with stipulations and penalties. I had an experience with terrible customer service and a poor signal, so I wanted to quit my contract. It cost me $250 dollars to get free when all of their charges were figured out. This was especially horrible because I didn’t even get a “free” cell phone through them. I paid for mine outright. I swore never to do a contract again.