I purchased k4 note about 1 year ago at the starting time it was working really great as the dolby atoms brought really good music experience and everything was fine even 3000mah battery was working fine but after 6 months its battery backup was decreasing fastly and now it doesnt even last 2 hpurs properly . Lenovo was supposed for good battery backup but for this product they let everyone down its made me fell really bad . And other features were good ram is still awesome 3gb works smooth and they could have increased the internal storage 16 gb is slightly less .