Forgotten pin or passcode?
Forgotten Passcode for 'Show Settings' in Kiosk Pro
If you've set your 'Show Settings' to show 'On Touch Gesture and Passcode' but have forgotten your passcode, unless you are using Remote Update of Settings (in which case, you would simply need to check or change the passcode in your .xml file), you will need to delete and re-install Kiosk Pro. As long as you have access to the Apple ID and password used to initially purchase the app, iTunes will have a record of the purchase, allowing you to reinstall the app free of charge.
Forgotten Passcode for Guided Access
If you're using Guided Access to lock down your iPad to Kiosk Pro, but have forgotten your pin, you may be able to exit Guided Access mode through a hard reboot. This method requires that you have a lock-screen passcode set on the device or have the 'Find My Phone' app installed and connected to an iCloud account (which allows you to set a lock-screen passcode remotely at icloud.com).
Once you have a lock-screen passcode set, you can force a reboot by pressing the Home and power buttons simultaneously until the device shuts down. Then use the power key to turn the device on again - it will boot to the lock screen and, once unlocked with the correct passcode, will return to the Home screen.
If you are unable to set a lock-screen passcode, a hard reboot will return you to the app and the device will remain in Guided Access mode. To exit Guided Access, you will need to unplug your iPad and allow the battery to drain to 0%, shutting down the device. When the device is plugged in again, it will boot to the Home screen. Alternately, you can restore your device to factory settings, which will wipe your device of all content and data (you will need to reinstall and reconfigure the app).
Forgotten Passcode for Restrictions
If the iPad you are using has specific iOS Restrictions enabled, but you have forgotten the pin, you will need to restore your device to factory settings, which will wipe your device of all content and data (you will need to reinstall and reconfigure the app).
Planning: How to Prevent This Issue Moving Forward
You may want to consider labeling the back of each iPad with any necessary information to access/update it, including the Apple ID and password associated with the iPad, the lock screen passcode, and Kiosk Pro's settings passcode. If the device is secured within an enclosure, this information is only accessible to those who can unlock and remove the tablet, but is right there if a staff member forgets. If your set-up precludes including this information directly on the back of the device, you could still add a label with the location or contact person for the info.
More generally as a best practice, we also recommend creating a time capsule with all the necessary project information to prevent headaches for anyone else picking up a project down the line.