Instrument Design Hints

You can include any fields and images (including signatures).
You can’t include video or audio as those will not be downloaded.
You can’t include external PDFs as those will not be downloaded.
Signatures will be downloaded as those seem important enough information for a small amount of bytes.
Regular file fields will not be downloaded. Their filenames and sizes will attempt to be downloaded.
Don’t make your forms too long. Shorter (< 100 fields) fields seem to work better with users. 1000+ field forms can induce frustration. Making your form too long can crash your device. Break up a long form into smaller forms and use the “Save and Go to Next Instrument” button.
Heavy amounts of branching logic and calculations will slow down the rendering of your form.

Device Hints

The most popular Android devices are the Google Nexus 7/9 and the Samsung Galaxy Tablet.
Android devices handle large projects better, for some reason.
iOS devices receive the best marks for hardware, but they are also the most expensive.
Android devices have more of a global appeal because Google is in more countries than Apple.
WiFi-only devices are ok in places where WiFi is readily accessible. Devices that support data transmission over cellular networks are required for places without much WiFi.

Common Setup Problem Hints

Could not get form rights (B)! This means that it could not access your server for some reason (often a firewall). If there is no firewall, retrying the process will often work.
Timing out on downloads. There are about 5-10 different download queries that happen to your server. If one of these fails, the app will fail to proceed. Often, there is no error message. It just dies. Try finding a spot with better Internet access.
Does not recognize QR code. Sometimes, the camera of your device will stubbornly not recognize the QR code. Here, you have to revert to the Alternate Method of setting up the project.

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