I received my iPhone 6 the Monday after they shipped, so I have had some time now to evaluate how well it works for me. Now before I go on I need to say something about iPhone 6 vs iPhone 6 plus. I bought the iPhone 6 but i'm still not sure which one is right for me. I'm 69 years old and screen real estate is important when you need a larger text size. I need to balance that with the habit of wearing my phones in a hip leather case. The 6 plus is so large that it looks ridiculous in a hip case, in my opinion. So I would have to carry it in a pocket. That was my decision factor in choosing the smaller iPhone 6.
This past year I have carried an iPhone 5s and I have loved it. During the year I tried son Android phones for a short time and kept coming back to the 5s. Its ease of use and uncluttered menus were the right choice for me and I think for seniors in general. However I also have a iPad mini and used it a lot because of the iPhone 5s's small screen size.
The iPhone 6 is a very good ballence between ease of carry and usability vs screen size. I love the fact that I can leave the iPad home and do everything that I need on the iPhone 6. I can size the type to my needs and still have plenty of screen. This is a phone that I highly recommend to seniors.