Why the Sony Xperia ZR
Rugged: IP58 certified - dust and water proof, Water resistant over 1 meter
Quad-core Qualcomm Snapdragon APQ8064 (1.5G) with Adreno 320 GPU, 2GB RAM (Same as the Nexus 4)
4.55-inch 720p display, a compact phone with good pixel density
13MP camera (slightly better cam than Nexus 4) Storage expansion option, FM Radio & 2300 mAh battery pack.
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It is compact, has an excellent screen, fast and intuitive OS. The only sacrifice you make it not having the same large App library as Android and iOS devices.
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