Cydia provides a
graphical user interface (GUI) to
jailbroken devices using
Advanced Packaging Tool (a
package manager) repositories to install software unavailable on the
App Store. Cydia is based on
UIKit and was written by Jay Freeman after porting APT to iOS as part of his Telesphoreo project. Packages are downloaded through the list of repositories a user has installed. Apps are installed in the same location as
Apple's own applications, in the /Applications
directory. Jailbroken devices can also still buy and download apps normally from the official App Store. Some
jailbreaking tools install Cydia automatically, while others may not.
Software availability Some of the packages available through Cydia are standard applications, while most packages are extensions and modifications for the iOS interface and for apps in the iOS ecosystem. Some Cydia repositories host open source packages as well as paid modifications for jailbroken devices. These modifications are based on a framework called Cydia Substrate (formally MobileSubstrate). Many ports of existing
POSIX-compliant command line tools are available on Cydia as well, including
bash,
coreutils and
OpenSSH, meaning the device could potentially be used as a full-fledged
BSD workstation, although missing some development tools.
Cydia Store In March 2009, the now-defunct blog
TUAW (The Unofficial Apple Weblog) announced that the Cydia Store, the in-app software purchasing system for Cydia, had opened for sales. The announcement also mentioned that
Amazon payments was the only option available, but that
PayPal would be added in the future. PayPal later became a payment option as well. Cydia stopped accepting Amazon Payments in 2015, leaving PayPal as the sole payment option. After a bug related to PayPal's digital token authorization was discovered via
TechCrunch, Freeman decided to shut down the Cydia Store on December 16, 2018.
Security The risks in jailbreaking are mixed. Advocates offer that developer tools installed from Cydia can help add extra security. However, being able to install untrusted third-party software can cause data loss and malware. Cydia Substrate, the code injection library usually installed alongside Cydia, will detect if an installed package causes
SpringBoard to crash, and will reboot it in a "
safe mode", with all third-party packages temporarily disabled. == History ==