hi ayden, first a question or two: What kind of computer are you working on" Which version of operatingsystem? What is the displaysize/screen resolution? i.g. you may be using a Samsung stand alone computer or laptop; you may be running Windows XP or Vista; and your screen may have a maxpixel set of 800 x 600.
I am using a Samsung Ultrabook with Windows 8.1 and a screenresolution of 1366 x 768. Having a Gmail account was sufficient for me to enter the google store.
Of course buying an app costs some money and then a PayPal account kicks in quite dandy. I can't compare Amazon and googlestore apps, but having been an Amazon bookreader for over a decade I do have an acount with them and a suitable credit card pay method has been established since I first joined them. The Amazon store showing the iRealPro app however sold for over $10US, whereas the Google playstore had the same app for way under. So now I work (as posted before) on my WP8.1 ultrabook with Bluestacks (the original program straight from their website) Mind: Bluestacks must be up and running before starting iRealPro. iRealPro only works on Android and Bluestacks emulates that. Recuperating: I bought the iRealPro app in the googleplay store from within the Bluestacks program; so the playstore saw me as an Android user. Logging in with my Gmail emailadress and password made me a respected customer. Using the forum can be done from outside the Android environment straight on the forum site. Only thing is you cannot play or see the charts. Tht only works from within the Android environment. Hope all of this makes sense to you. I'm happy being able to get an email through Gmail in the Android environment and by clicking the link to a tune see iRealPlay open up and show the chart. Change a chord here and there and send it right back to my buddy for a review.