Hi Chen, ... You say you've already chosen Qualcomm (which isn't necessarily a bad thing depending on your target audience) but I've a few comments on your summary of SoCs which you may want to take into consideration. Intel have indeed exited the mobile chipset business however China-based mobile chip vendor Spreadtrum have partnered with Intel and have been making new x86-based SoCs for smartphones. Allwinner is quite the opposite of what you describe. They are actually one of the best vendors for non-Android support and use Mali GPUs which are compatible with the Lima free/open drivers. You didn't mention OMAP, perhaps because TI are no longer developing new chips, but OMAP has great mainline Linux support. The main disadvantage with OMAP is the PowerVR GPU for which there are no free/open drivers. Qualcomm has traditionally been a bad choice for privacy reasons. Their SoCs are known to have bad hardware design where the modem controls GPS, audio (including mic), RAM, NAND. If you choose a Qualcomm SoC without a built-in modem, it might be okay. Mainline Linux support for certain Qualcomm SoCs has improved in recent years and Freedreno (along with Lima) is one of the more advanced projects for free/open GPU drivers. Have a look at my thread on mainline Linux devices which provides some info on which SoCs are currently best supported by mainline Linux. There are currently two 64-bit Qualcomm phones with some support: the LG Nexus 5X (MSM8992) and the Huawei Nexus 6P (MSM8994). Other 64-bit Qualcomm chips with mainline support can be found here.