California’s attorney general has begun notifying “scores” of app developers and companies that they are not in compliance with the state’s privacy law.

Kamala Harris has given those involved 30 days to “conspicuously” post a privacy policy within apps which informs users about the personally identifiable information collected about them, and what will be done with it subsequently.

Some 100 companies are being targeted, starting with “those who have the most popular apps available on mobile platforms”.

The letters are the first step in legal action to enforce the California Online Privacy Protection Act, which requires commercial operators of online services which collect personally identifiable information – including mobile and social apps – to clearly post privacy policies.

Companies can face fines of US$2,500 each time a non-complaint app is downloaded.

The action follows an agreement Harris forged among “the seven leading mobile and social app platforms to improve privacy protections for millions of users around the globe who use apps on their smartphones, tablets and other electronic devices”.

The companies inking the deal – Amazon, Apple, Facebook, Google, Hewlett-Packard, Microsoft, and Research in Motion – agreed to privacy principles designed to bring the industry in line with California law requiring mobile apps that collect personal information to have a privacy policy.