Editorial methodology

Sources and limits

We cite primary research where available. A library record can verify publication details without giving access to a work. A meta-analysis summarizes studies; it does not prove that a particular app or routine works. We state when we cannot verify a claim.

Practical advice

Examples and schedules on this site illustrate choices. They are not tested courses or guarantees of proficiency. We do not convert hours into a promised level.

Our product

We use official product pages for app features and prices. We disclose ownership and describe limits. This site and the related guides are not independent endorsements.