As ChipWorks noted in their recent Galaxy S6 analysis, more and more of the chips in Samsung's flagship phones seem to be originating in-house. On the front side of the mobo, we find:

Samsung Exynos 7420 Octa-core Processor - 64-bit, 2.1 GHz Quad + 1.5 GHz Quad, with Samsung K3RG3G30MM-DGCH 3 GB LPDDR4 RAM layered in

Samsung KLUBG4G1BD 32GB NAND Flash

Skyworks 78041 Hybrid Multimode Multiband (MMMB) Front-End Module (FEM)

Avago AFEM-9020 PAM

Wolfson Microelectronics WM1840 Audio Codec and Maxim MAX98505 Class DG Audio Amplifier

Samsung N5DDPS3 - Similar to the N5DDPS2 spotted in the Galaxy S6, likely NFC Controller

InvenSense MP65M 6-Axis Accel + Gyro, and Samsung C2N89U (likely image processor)