I found a project offering an airdrop but required participants to download and install their mobile app. The app is newly made with only few hundreds download and I don't think I'll ever use it.
Is it too risky?
i don't have interest such project because most of the project that requires App's are not good. although some airdrops are also good but those good once can not give you reasonable and exchangeable token.
In some part you are right that most of those coins are not that valuable and sometimes we are just getting tokens that haven't got any value or could not be sell but we need to remember that not every air has the same and sometimes it is not a bad idea to just risk some time to gain some nice tokens.