Am I correct in that because I have two different platforms on my two devices Ios (apple) and android(samsung). I will have to pay $20 for each device
That's correct.
If so this is a real bummer!
Why? They're two different applications distributed by two different companies, Apple and Google.. If you want two different applications, you have to pay for two different applications.
For wat we spend on trains, an extra $24.99 (the actual price) is peanuts.