Filemaker Go can not host a file. Filemaker Go can connect to a hosted database just as a computer can. iPad or iPhone would not be fast enough to host a databases. You can host the file on your own computer at home using filemaker. You will have to setup port forwarding to access your database from outside your local network. http://help.filemaker.com/app/answers/detail/a_id/9770/~/port-forwarding-information
iCloud really isn't a full file service yet or it's under way. It's not as far a long as dropbox. You can use dropbox to copy your file from your home computer to your device and then back your device to your computer.
Dropbox seems to work fine with Filemaker Go as far as downloading and reading the file (aside from the fact that Dropbox keeps trying to build a preview of the file, and if I let it work too long it will crash); but if I want to make changes and upload the changed file back to Dropbox I don't see a way to do it. Filemaker Go imports the file from Dropbox and apparently stores a copy in it's own area. The original in DropBox is unchanged. The FMG "Save" command only lets me save a copy (of the changed file) back to the same private FMG directory, or email it.
The file service I use most of the time is SugarSync. I also use Dropbox and on my iPhone 5 the preview just state it "Couldn't Load File'.
You will need Filemaker Go 13 to transfer file to your computer with Dropbox and other supported file services.
Steps for iPhone
1) In Filemaker Go select the Device icon at the bottom of the screen, the will take you to "Files on iPhone" (Go Files)
2) Then select the icon at the top of the screen that look like a piece of paper folded with a check mark in it.
3) Select the file you want to sent to dropbox or other file service.
4) Select the icon at the top of the screen with the arrow point up out of a box.
5) Select "Open in Dropbox" or other supported File Service.
6) Then you navigate to a folder or leave in default location in dropbox then click save.
Steps are a little different on iPad, which I don't currently have with me, but later today I will put step-by-step instructions for it.
I forgot to mention
You may need to update dropbox or delete and reinstall dropbox if it keeps crashing. I have not tested any large databases, so it may be a bug in dropbox preview with large files. You may want to try www.sugarsync.com instead.
Yes, so far I can't get FMG13 to "open" the file in DropBox. I get as far as selecting DropBox as the application to open my FM file, then my iPad hangs... I have to double-click the Home button and quit FMG13 to fix it.
I would make sure all the software is update : Filemaker Go, Dropbox and ios. I tested a sample database with no freezing or hangs. To be on the safe side, I would remove Go and Dropbox and install them again with the newest versions. If it is a large database it may take some time, so I would give it about 15 minutes or so..., because it might just be slow copying.
Step to transfer file from iPad
1) Select Device icon on left in Filemaker Go
2) From "Files on iPad" select the icon at the top right that look like a folded piece of paper with a check mark.
3) Select the file the file you want to transfer
4) Select the icon top left of screen with an arrow point up out of a box.
5) Select "Open In DropBox"
6) Choose a different folder or leave in the default location and click save.
Wasn't really that much different than on the iPhone, but I put the steps, just incase someone may need the steps.