Appodeal must has a lot of free $ in pocket
I meant that if they catch 10 big developers which will generate for example $1000/day each. So, we have $10k/day. As I remember AdMob has NET20 - $ for January AdMob will send 20th February. -> As I understand Appodeal showing ads from AdMob and other ad networks, so they will receive revenue from these ad networks on their NET terms.
Conclusion: If 10 big developers will payout revenue in 30th January, Appodeal must pay $300k (if each big developer will get $1000/day). This is a lot of money which they never retrieve, because they receive 20th February $300k from admob and in meantime payouts more to other developers. They always will invest more $ than receive from admob and other networks, unless they can receive $ from admob in 1 day.
For me this is risky, because this is not a business model!