Hi friends, I am a frequent buyer of mobile phones & generally suggest my friends & family members. My tips are under :
Operating System Platform :
3 Major OS platforms are Android , iOS ( Exclusive for Apple mobiles) , Windows ( Least preffered these days) . Though blackberry OS is also there but it is now almost out of Indian market. But if you are high profile individual then its still the most secured & reliable OS.
Your Budget :
Then plan your budget as per your requirement. Generally good Android based devices start at 8000 INR & iOS based Apple devices would fetch 30000+ that too for old models.
Brand Finalization:
Then select your brand. These days Mi, Oppo, Vivo are outperforming the Android market in the range of 8-15K. Though Samsung is still there with J series & On series. Take care of the service center aspect nearby your location of you are looking for Vivo, Oppo or Mi. Generally Samsung has good service network.
Hardware & Memory :
Check the screen size as per your suitability. Also check if its HD or Full HD.
Make sure the internal storage memory is sufficient for you. If you plan to extend data in future, it should have expendable memory slot. Note that Apple is not having expendable memory. Though it comes with standard variants like 16-32-64-128-256GB.
Always check the battery life, more the mAh more the phone would run without charging.
Check if your headset support latest 4G carrier band, else latest sims with great plans like Jio won’t run.
Check for Exchange offer if any :
In the last, make sure to check out with your retailer if he is willing to take your old phone at good price. Check once at OLX regarding prices. Though online websites are also giving exchange offers these days.