"Sinónimos y Antónimos Español" is an Android-based dictionary developed by Networks Pe. It falls under the category of Education & Reference and is available for free. The dictionary contains a whopping 45,099 words and 387,285 synonyms and antonyms. One of the biggest advantages of this dictionary is that it works offline, and can be accessed at any time without the need for an internet connection.

The app has a simple and user-friendly interface, making it easy to search for words and their synonyms/antonyms. The app allows users to quickly find the meaning of a word and expand their vocabulary with the help of synonyms and antonyms. Overall, "Sinónimos y Antónimos Español" is a useful tool for those looking to improve their Spanish vocabulary.