A free program for Android, by Magnetic Lab.

IMG2PDF is an easy-to-use application that allows you to convert multiple images into one PDF document. This is a very useful app for those who need to send invoices, receipts, certificates, etc. to their customers. It is also useful for those who need to send an official document to the authorities.

With this app, you can easily create PDFs from your photos, making it easier for you to send them via email or other means. 

IMG2PDF comes with a user-friendly interface, which makes the app easy to use.