I think the bigger problem is because, like your aware, that you would need a lot of capital to compete with the major telco/cell companies like the ones listed, it would be more reasonable to create a company that requires less funding by starting with a smaller market to fine tune the company and then seek out larger investors. The problem with this is that even though you won't be initially concerned about the competition from Sprint, Verizon, AT&T, and Tmobile as you would be applying yourself to a less mainstream (aka: different) market, there are still many competitors that have 'fixed' the complaints about the big companies who have a head start over you (ie: Boost Movile, Cricket, even Virgin Mobile). So unless you have an idea superior to these smaller upcoming companies, it will be a very difficult industry to enter in to and raise capital for.