Side By Side Comparison of Oppo R1S and HTC Desire 520. Compare Processor, display, RAM, Storage and other features here. You can quickly compare Oppo R1S and HTC Desire 520 smartphones just by looking at their ratings and results showing "winner" and "runner up." There is also a short analysis comparing different features of Oppo R1S and . You can also look at each hardware feature individually to perform your analysis while comparing mobile phones.