There are two giants in the market, Apple and Samsung. Both have different technology operating systems running there phones like iOS and Android. If the money is not an issue then you can buy any latest mobile of these two companies to get optimal experience. Since i am a android fan from the beginning so i will recommend to go with a phone with android operating system. this will help you get maximum apps from google play store for free, which is relatively cheaper from iPhone. If you are on a budget then there are many cool brands available in the market with the same specs as the flagship phones from these two companies (Samsung, Apple) but on a lighter burden on your pocket. Some of the more successful new comers are Huawei, Xiaomi and Oppo. Since there are a lots of phone models to go between them so i will recommend consulting a smartphone comparison website. I found about these mobile comparison websites through this article revglue(.)com/blog-detail/13-setup-free-uk-mobile-comparison-website although i didn't get the chance to compare my self since i always go for the samsung mobiles which are my favorites. Good luck with your new mobile. oh i forget to mention HTC too although this brand has lost his popularity due to high competition but it is still a good company which is manufacturing some solid phones.