How to Update Cydia in Background on iPhone, iPad and iPod touch
Unfortunately, Cydia still doesn’t support the native multitasking / backgrounding feature which Apple introduced with iOS 4.x last year. What this means is that Cydia updates are installed whenever you start the app, followed by those annoying “Reloading Data” screens.
Thanks to some SBSettings toggles, you can now update Cydia in the background while you check your email, or reply to an important text message, and then quickly go back to it when it is done with all the updates !
Note: You must install SBSettings from Cydia before installing the toggles mentioned below.
Debian Updater for SBSettings
Debian Updater is a toggle for SBSettings to update in background the package database reflecting your newest sources.list file. In other words, you can refresh your Cydia source list everywhere (on Springboard or lockscreen, or within any app), without launching Cydia app.
Aptupdate for SBSettings
This toggle updates and upgrades your Apt cache and packages in the background. All you have to do is to press the button and you are free to do something else while your phone updates.