Hêng-tōng app (Eng-gí: mobile app) ia̍h sī kóng Hêng-tōng èng-iōng (mobile application), sī chi̍t khoán siat-kè beh kiâⁿ tī hêng-tōng chong-tì chhan-chhiūⁿ tiān-ōe/tablet ia̍h póe-á ê tiān-náu thêng-sek he̍k-chiá sī nńg-thé èng-iōng thêng-sek (software application). Tāi-seng app sī khai-hoat tī seng-sán-sèng ê hū-chō͘ pí-lūn Email, la̍h-ji̍t (calendar), liân-lo̍k chu-liāu-khò͘, tè-bóe koh hoat-tián chhut chē-chē khoán-chè, pí-lūn hêng-tōng gém, kang-tiûⁿ chū-tōng-hòa, GPS kap só͘-chāi ki-chhó͘ ho̍k-bū (location-based services), chù-bûn tui-jip (order-tracking), bé-phiò, ū kúi pa̍h-bān khoán ê app tī--leh.

App it-poaⁿ sī ài tùi èng-iōng hoat-pò͘ pêng-tâi téng táuⁿ-ló͘, chia ê pêng-tâi chú-iàu sī hêng-tông cho̍k-gia̍p hē-thóng ê chhî-iú-chiá leh ūn-choán, ū pí-lūn App Store (iOS) ia̍h Google Play Store. Ū-ê app sī bián-hùi--ê, ia̍h ū ê ài khai-chîⁿ, bē app ê lī-ek sī hia èng-iōng ê chhòng-chō-chiá kap hoat-pò͘ pêng-tâi thiah siàu.