The Galaxy J3 (2017) welcomes company - the 5.5” Galaxy J7 (2017) and the 5.2” Galaxy J5 (2017). All of them run Android 7.0 Nougat with Samsung's custom UI on top.
Note that Samsung seems to have jumped the gun with this announcement, the J5 and J7 are not up on the company site yet (well, not where they should be, anyway).
The Samsung Galaxy J7 (2017) boasts splash resistance (IP54), which the other two lack. It’s also the only one with a 1080p screen (5.5”), though the whole family comes with Super AMOLED panels. Plus, it uses a modern USB-C port (the other two have microUSB).
Beyond that, there are many similarities within the new J series. They stick to the Galaxy S7-like design (no S8 Infinity display magic). Both the J7 and J5 have a fingerprint reading Home keys below their screens, 5.2” 720p for the J5.
Samsung Galaxy J7 (2017) in Black and in Gold
The main cameras are identical, 13MP main camera with 1080p video capture and a bright f/1.9 aperture. For selfies, you get an impressive 13MP camera with its own flash.
Processing power is similar, both are based on the Exynos 7870 chipset (14nm, 8x A53, Mali-T830 MP2) and both have 16GB of storage. However, the J7 has 3GB of RAM while the J5 only has 2GB. Battery capacity differs as well, 3,600mAh and 3,000mAh respectively.
The Galaxy J5 (2017) will come first (by the end of the month) at €280 while the Galaxy J7 (2017) should launch in July for €340.
The Galaxy J3 (2017) is already available on AT&T, but it’s coming to Europe in August. Curiously, it comes with a different design (the back) and slightly different specs. It should cost €220. It has a 5” 720p Super AMOLED screen, quad-core processor, but the Euro model is much better specced than the AT&T one (it's practically a different phone). You get a 13MP f/1.9 main camera (vs. 5MP) with a 13MP selfie with flash (vs. 2MP), slightly more RAM (2GB vs. 1.5GB), NFC, a slightly smaller battery (2,400mAh vs. 2,600mAh).
Via (in Dutch)