Products are digital, delivered by email after payment, licensed for your personal or business use, including use inside your own commercial projects; do not resell, share or republish the product itself (a license file in the download, where there is one, gives the details). Purchases are one-time and include 30 days of free updates. Refunds: email support@tinytank.app within 14 days of purchase and we will review it promptly and refund the price paid unless the content was clearly redistributed. Free updates for 30 days mean any new edition of the same title is emailed to your purchase address; separate volumes are separate products. Content is provided as-is without warranty. Free browser tools and apps (under /apps/ and /tools/) are free to use for personal or internal business use (you may share the output they create, such as images and cards), provided as-is without warranty, may change or be withdrawn at any time, and are not medical devices or medical advice. tinytank.app is operated by Yang Xuejin (杨雪晋), an independent developer (individual, no company). Contact: support@tinytank.app.