Web apps for data collection

Data collection today is done on a wide variety of hardware (tablets, iPads, phones, etc). Rather than writing an app for each type of machine it makes more sense to write a web app for data collection needs. That way I only need to write one app and it will work on any machine with a browser and web connection. The problem comes when internet access is lost. Data collection in timberland is oftentimes many miles from a web connection. The “no service” message on my iPhone is quite common.

For those developers who have faced this problem, what was your solution? Thank you, TJ