A free program for Android, by Widget7.

The PPTX to Video app allows you to convert PowerPoint presentations to MP4 video. It has an easy-to-use interface and supports many themes. It supports audio recording and mixing. You can select the audio, video and text to be included in the final video. Moreover, you can add your own background music and sound effects to the file. You can add background music from your device or add your own music. You can add background effects like a fade effect or a watermark.

To create a presentation using this app, you need to install the app and select the file. You need to select a theme to create your presentation in. You can select the audio, video, and text. After that, you need to click on the convert button to convert the file. You can preview the file.