Updating data on a mobile device

Now that you have a database on your mobile device, we will mention some of the techniques you can use to edit and save data as there are a few differences from desktop-based applications.

First, you're probably accustomed to presenting a screen filled with edit fields and allowing the customer to click OK or Cancel to decide whether to keep the changes they've made or discard them all. Mobile device users expect everything to always be saved automatically. In fact, the Apple guidelines for app design encourage fluidity to help users interact with their devices in a smooth and seamless manner; stopping to ask for confirmation should only be done when essential to prevent the loss of data or to alert the user to an important notice or decision to be made. For example, a point-of-sale application should allow a receipt-in-progress to be tendered or canceled, depending on the customer's choice to proceed with the purchase, but a change...