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I have 2 micro cloths. One I damp then wipe my iPhone. Then I use the dry micro is buff it up.
 
No chemicals or solvents required. Just a microfiber cloth and moisture from your breath, if required. If you eat while using your phone you might want to "slightly" dampen the corner of your cloth.

I also like to take my case off very few weeks or so to remove any accumulated grit that can act as an abrasive if caught between your phone and case. It can and will actually "scuff" the finish.
 
No chemicals or solvents required. Just a microfiber cloth and moisture from your breath, if required. If you eat while using your phone you might want to "slightly" dampen the corner of your cloth.

I also like to take my case off very few weeks or so to remove any accumulated grit that can act as an abrasive if caught between your phone and case. It can and will actually "scuff" the finish.
What is the best brand
 
What is the best brand

You can buy them on Amazon in bulk. I think I got like 50 towels that were 18" X 18" for like $20. They might cost more but you can get them at auto parts stores also. They will not scratch anything. They are washable and can be reused over and over. The better half uses them as napkins at dinner parties.
 
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