I am new to Android and with my new GNex, I am excited to start downloading some apps. My question is it safe to assume that a free app with no pay versions or upgrades/subscriptions will most likely support ads? For example AirDroid. It seems to be completely free with no additional paid options. I am sure the developer hasn't put the effort into such an app and independent website out of the kindness of their heart right? I would rather steer clear of apps that may support ads then have to seek out the culprit when an ad pops up after the fact. Thanks!