S7 samsung galaxy phone would probably be the best phone currently, and if needed one good but the prices are extremely reasonable, the Xiaomi MI5 is a best choice
Depend on your requirement!
If you want to have a mobile app that serve for business purpose. You should choose Samsung Galaxy Note. Because its technology and capability are designed for merchants.
If you want to own a luxury mobile app that is only for normal function (office, surfing Internet,...) you should choose Iphone.