Improve my php code - to mobile optimized version with progress bar and modern looks

I already have a working php page which i have integrated in my android app, using web view. Attached screenshot is how it looks now. I would like you to improve the php code for modern look, please add a nice uploading progress view and when its done, it should show file successfully uploaded notice and then return back to same page incase user wants to upload more. If you are well versed with PHP you shall understand the code by looking at it, the user selects the category, selects file, selects file image and then uploads it to my FTP server. After it is uploaded to FTP a database query is called. All this code is already written in my PHP file. Is there any better method than i am using "move_uploaded_file" function to upload file. As this thing works slow on my shared server for large files. If you have better PHP codes like uppy.io then i would love it to be integrated, not sure how it will be done but up to you.
It will be a one page PHP file with html code already which i will share with you after i am satisfied you can carry the job.
Please do not apply with standard cut paste information, let me know how will you go about it and if there are some examples.