I have used a Samsung Galaxy Note 4 for quite a few months and although I have generally been very happy with it, it does feel that the OS is not fully optimised. When I recently purchased a Nexus 6 and having used that phone for a few day, my gut feeling got confirmed.
The Nexus 6 and the Note 4 have the same basic specs: same screen resolution, same processor, same amount of RAM. However their performance is not the same. Now, I did not expect it to be the same, because the Nexus 6 is the cleanest Android version available, whereas the Note 4 is a highly modified version of Android.
To check performance I launched multiple apps sequentially and compared the speed. Overall, they were just as capable. I had not expected this and was pleasantly surprised by the Note’s performance. However, the big difference – and you notice it in daily use – is how well the phones multitasks. We know that TouchWiz is not a light implementation of Android, and the photo below shows the available RAM at startup.
The Nexus 6 (on the left in the picture) has 800MB more available RAM and start-up. In day to day use this means that you can load apps much more frequently from RAM and that really helps generate a more fluid user experience.
I realise Samsung will improve the Note 4 ROM, and given that they are taking a long time with the 5.1.1 update, I hope they take of this to a large extend.