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> I got on e-mail from one guy from apkfiles.com and he asked me if I could submit my apps there. Sounds legit, but need some feedback first.
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that is free market android, you'd exposing your .apk source directly to be stolen dont use those type of markets, i use those type of markets to unzip the apk and see how games are made and what is the logic in the code,(plus most 2d games on android market leave their assets exposed in the .apk when u unzip the apk if its not using some server to download the data/images/media all files are inside and you can do what ever you want to them... ie. make a different clone with exact graphic/media assets... ) ... while if you host your game on gplay you dont have a direct access to the apk file.. but the game is installed from a temporary file which is then deleted upon installation.
however you can try opera market as well. they are pretty big, and there is a buying market for games there, not as big as gplay but big enough that counts. and of course amazon as mentioned above should be big enough to share your product around.
Anyone who downloads your app can get the .apk file - it's not like these alternative app stores reveal anything extra to anyone. Most of them will index your app from Google play anyways. I've downloaded hundreds of apps from sites like apkjoy.com and apkfiles, apkpure etc. and have never had any issues - you can verify the app is legit by verifying the signature - that can't be faked.
On another note I've also promoted my own (and clients) apps on these sites, and while submitting your app for free may not get any exposure I was able to drive thousands of downloads to my apps at about $0.53 CPI (cost per install) which is about HALF of the industry average.