I have been using htc 620 g from last 2 years . its sound quality is very poor . we can not hear the real sound . although it is very easy to use as all the app are on the home page . I do not like the style and design of this phone if we compare with mi 4 . it provide only 1 gb ram thatbis not succient as it cause hanging problem. also low camrea quality . the battery backup is only for 5 hrs . that is very low . at the range of 120000 I m not satisfy with this mobile . so I suggest to go for its higher models .