I'm trying to achieve the same thing although it seems like we need external cumbersome application like . I've put in a feature request since I believe it is not possible today without the external app.
Some reference here :
CNSBarcode is an app that has most of the problems worked out and they have an app for ios and a plugin for Filemaker Pro.
pic2Shop has a free version and a pro version app that willl scan and work with Filemaker Go.
I also agree that this is something that should be native in Filemaker Go since the second app idea using a URL is cumbersome and troubled. Anyone trying to do inventory bar code scanning with an iPhone will soon look for another method after witnessing the delays and annoying swinging windows a few hundred times.
This swinging door when using Safari gets annoying real fast and kudos and lolipops should go to the Filemaker engineer who discovers how to avoid this and just get the scan.
i found an app called barcode 2 sql at app store.
free to download and cool design.
check the website also barcode2sql.com
I'm not sure if Filemaker has built-in barcode scanning component. If no, you can install a barcode reader for IOS, it'll scann and read most types of 1D and 2D barcodes. Open sources are not difficult to get on Google.
With FileMaker 13, you can now use the Insert From Device script step to scan a barcode directly into a text field using the device's camera.