I used many phones but the worst one is Nokia x I used it before 2 years and I am totally dissatisfied with the phone. the operating system and features given in the phone are not user friendly. it is very difficult to understand the features of the phone.
Someone who is using smartphone for first time I recommend him to dont buy Nokia x. the screen size of the phone is 4 inches and it supports HD videos but if you play HD video it is mostly unable to p[lay the video and get hanged and automatically get switched off. the sound quality is only think that I can say is good about this phone. the worst thing in this phone is the battery which is only 1500 mah which gives a battery backup up to only 8 hours so you need to charge the phone regularly or you must need to buy a power bank for power support. so dont buy this phone this not money worthy.