Three devices that cater from 4.5 inches to 5.5 inch screen sizes. They do vary a bit on processing power and connection speeds. Here's an infograph from Samsung itself comparing the 3 - To keep it simple, the A3 and the A5 share the same processor, but different screen resolutions/sizes. The A3 has a 540x960 resolution screen, which in my opinion is okay for the screen size. the A5 has a 720x1280 screen resolution. Where this might work is in the battery life they manage from the 1900 mAH and 2300 mAH batteries respectively. The A7 uses two different type of processors, one with a Quad 1.8 Ghz and a Quad 1.5 Ghz processor (Snapdragon 615) for the LTE variant and a Quad 1.5 Ghz + Quad 1.0 Ghz Exynos processor for the LTE/3G Dual SIM variant. The A7 packs a Full HD 1920x1080 screen with a bigger 2600mAH battery. What I personally feel is this is Samsung's attempt to revamp their line up and to try and take on the lower segment vis-a-vis iPhone 5C/5S and the likes. Pricing is 20,500 - 25,000 - 30,400 (rumored for the A7) which does make these pricey options. I like the A3, which takes on the HTC One Mini at a much cheaper price point. Cheers
Source - [Infographic] Galaxy A3, A5, and A7 At A Glance – Samsung Electronics Official Blog: Samsung Tomorrow | Samsung Electronics Official Blog
I just saw the Samsung A5 at a store. And the damn thing is beautiful. (Never thought I would say this for a Samsung). And light! More details to follow in a separate thread.