Here is my personal experience:
On one device (Samsung J7, 1.5 Gb RAM) with average 500-600 MB RAM free, crashes are frequent (every second fight, impossible to access Empire HQ and Arena)
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On a second device (Samsung J5, 2015 model, 1.5 Gb RAM) with similar amount of free operative memory i encounter similar issues
Screenshot_20171209-100507.png
On a third device (Samsung J5, 2016 edition, 2Gb RAM) with average 1 Gb RAM free, the game runs without crashes most of the time (occasional crashes occurs after switching between different accounts and playing each of them)
Device memory before and after loading Galaxy Legend application:
Screenshot_20171209-100512.png
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As it can be seen, on spot the game requires at least 700MB of free RAM just to show the main interface. Sure, RAM is managed dynamically by OS, and some areas are unloaded (freed up) when it is required but, just i said in a post above, on Facebook i've seen a screenshot with 1.4 Gb RAM used by Galaxy Legend - definetely my devices with "only" 1.5 Gb RAM can't handle it)
Add here the fact that this application is using CPU and data traffic extensively (overheating of the device just as Triad mentioned is a good indicator for that) and you will come to the straightforward conclusion - sadly enough, such a great game is developed by a team of second hand coders with really greedy management
App devs should remember the famous "640K RAM ought to be enough for anybody."
If you're looking for a crash-free gaming experience with this game, either use emulators on PC or buy latest devices with large amount of RAM![]()