I hate to admit this as an engineer, but the people who make a difference are working at the strategy level and not the implementation level, which is where most of us engineers spend our time. No world-changing startup ever failed because "we couldn't get the code right" -- they fail because they build things the world doesn't want, or they fail to market the things they build to people who want them.
The second difficult-to-admit thing is that software is only good at solving problems where analyzing information and manipulating data are the solution. Mobile banking apps are doing tremendous good in developing countries -- but the benefits of things like mosquito nets, water purification, and vaccination are not software problems. I'm pretty doubtful that apps will do much to alleviate poverty, although I'm excited and encouraging of the people who are trying.
The second difficult-to-admit thing is that software is only good at solving problems where analyzing information and manipulating data are the solution. Mobile banking apps are doing tremendous good in developing countries -- but the benefits of things like mosquito nets, water purification, and vaccination are not software problems. I'm pretty doubtful that apps will do much to alleviate poverty, although I'm excited and encouraging of the people who are trying.