PReVo - Vortaro de Esperanto is a portable version of the Reta Vortaro, which is an Esperanto language dictionary. It is designed for Android users and is available for free under the GPLv2 license. One of the main features of this app is that it doesn't require an internet connection to use. The entire Reta Vortaro is available offline, and users can quickly search for words in Esperanto or translate them into other languages. The app includes translations into many languages, making it useful for Esperanto learners around the world. PReVo - Vortaro de Esperanto is a valuable resource for anyone who wants to learn Esperanto or improve their existing knowledge of the language.