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Here is a quick overview of the differences and Similarities
We will start with the physical appearance since here is where you will find the first noticeable difference,
the design was totally revamped the front facing camera was centrally placed and the device got a metallic trimming.
The C7 also got a curved/rounded back design.
Both have a 13 MP back/Rear camera which is supported by a dual flash the only difference that comes in is that camon C7 comes with a 13 MP front/selfie camera which is an upgrade from the 5MP found on the Camon C8.
The two phones have a front soft flash for taking selfies at night.
3. Processor & Ram
The C7 and the C8 are similar in terms of number of processors ( both powered by a quad core (4 cores) processor.
But in the operating memory the C7 is equipped with a 2GB ram against the 1GB found on the C8, this makes multi-tasking on the C7 much easier and seamless.
Both phones have a 16 GB internal storage, which is expandable up to 128 GB through a memory card
Both the phones have IPS Touchscreen with a screen resolution of 720 x 1280 which is HD(720p), the only difference is that the C7 has a lesser screan size of 5.0 INCH when compared to the 5.5 INCH on the C8
The C7 does not support LTE/4G network likewise the C8, but you get to enjoy the normal 3G in with normal upload and download speeds.
Both batteries are non-removable, though we have a 3,000 mAh battery on the C8 and a 2,500 mAh on the C7
Both batteries can last a whole day on normal usage.
8. Operating system
The C7 comes out of the box with HIOS based on Android 6.0 while the C8 has Android 5 lollipop though there is a Marshmallow + HIOS update for the Camon C8.