The galaxy s5 has a perfect size for all people even though some say it is to big. However my grandparents love this phone because it is easy for them read everything with it being the size that it is. Also the function is great at the beginning but it slows down just a little bit as the older it gets, but its hardly notice.e
This phone is very easy to use, but like with any technology, there are sometimes issues. It occasionally locks up. About once a week, I do a hard refresh and that seems to help with the majority b of the issues. I'm sure it's software and application issues anyway.