I used to use the S4 and I found that it's not bad at all, but I wanted to upgrade to Note 4. I bought a Note 4 last month, before I bought it I found a friend of mine using it and I thought it's so powerful device, then I decided to buy one. After buying it, I found that it's a powerful device and meet my demand 80%. The NOTE 5 has been released recently, but i found nothing is much different between the NOTE 4 and 5. There are some options in NOTE 4 should be improved is as following:
1) I explored online many times before I buy the NOTE 4, after buying it, then I realized that there are some options were missing. such as Video recording mode (This mode is allow you to take a Video with a smooth motion) this function on NOTE 4 is missing.
2) there is no highlighter on the NOTE 4 device. e.g. If you are reading docs, then you wish to highlight it, the you can't do that.
3) You cannot copy an image/photo to send as attachment on this NOTE 4. e.g. Once you find the interested image/photo, then you want to share with your friend, you cannot click and drop this image/photo to your message. Or you wish to copy that photo to another folders.
4) Samsung forum is useless, once you want to have a question and answer (Q&A), you don't know where to send the complaints or ideas. Recently, I dropped some questions to ask the Samsung or Android developers, there is no answer from them at all.