Responde Aí: Engenharia, Cálcu is an Android app designed to help students learn engineering and calculus in a convenient, efficient, and effective way. This app is developed by Responde Aí Tecnologia e Educação S.A. and is available for free. It falls under the category of Education & Reference. With Responde Aí, students can learn the concepts in minutes that would take hours otherwise.

The app offers offline access to all the content, allowing students to download and use it wherever they want. It provides lists and old exams solved step by step from the biggest universities of exact sciences in Brazil. The exercises are solved step by step, in order of difficulty, making it easy for students to understand the concepts. The summaries cover the entire matter, and the Aulões Salva-Vidas can help students go from zero to approval in just two hours. The explanations are direct to the point, available in both video and text format.