Indonesia's powerful anti-graft agency said Thursday it had launched a mobile app packed with graphics and games to educate the public and officials about bribery in one of the world's most corrupt countries.

The app, available for free on iPhones and handsets using the Android operating system, features a virtual theme park where animated graphics teach people about how to avoid giving out or receiving payments that could be considered kickbacks.

It also features quizzes to test people's knowledge of the issue.

"Many state officials and entrepreneurs are not aware that giving gifts and free services constitutes corruption and is an offence," Corruption Eradication Commission (KPK) spokesman Johan Budi told AFP.

Corruption is rampant in Indonesia, particularly in the bureaucracy, and it is common practice for officials to demand payments from members of the public for providing services that should be free.

While there is great public awareness and anger about high-level corruption involving huge sums of money and top officials -- and the KPK has succeeded in cracking some major cases -- lower-level corruption is more widespread and harder to fight.

Smartphone sales in Indonesia, which is the world's fourth most populous country with some 250 million people, have been surging in recent years as the middle class grows.

NGO Transparency International ranked Indonesia 114th out of 177 countries and territories in its annual corruption perceptions index last year. A number one ranking means the least corrupt.