NumisGallery turns world banknotes into a focused study experience on iPhone. Browse by country and denomination with simple directional gestures, open detailed note views for context and attribution, flip between obverse and reverse one side at a time, and long-press to reveal motif highlights during gallery viewing. The product is built for appreciation rather than transactions: no valuation, no trading, no export, no sharing, no printing, no ads, and no third-party analytics SDKs.