Here is a tip.
I was with a client, and we had to sign some documents and send them off quickly. So we signed them. Then I went to the post office to send them. Once at the post office, I realised that we had no copy of what we signed. If the letter got lost or was delayed, there would be no evidence that we had signed or sent it.
Standing in the queue in the post office, I could see it was a lousy environment to take photos, so I decided to experiment with the free Google PhotoScan app. So I took pictures of the documents, the addressed letter, then the documents partly in the letter and then the sealed letter. Overall I was stunned how good the quality of the scan of these documents produced considering the bad lighting and lack of space. So I thought that if it was useful to me, that many of my clients here who need to scan documents and do not right then have access to a flatbed scanner would find it useful too.
It actually what it does is get you to take five pictures of the document from different angles and using its smarts to fix the photos to make one good scan. What stunned me was how well it reduced the light spots that regular photos so often produce.
It is the best app, I have come across to scan documents via phone.
If you want to investigate, click here.
Note I tried it on photos with mixed success.