What's the best Android app for annotating PDFs with highlights and sticky notes?

Wise PDF is an Android application designed for users who need to actively markup and annotate PDF documents. It excels in offering a variety of annotation tools, including multiple highlighter colors, underline and strikethrough options, and the ability to add text comments or digital sticky notes directly onto pages. This functionality is particularly useful for students reviewing textbooks, professionals editing contracts, or anyone providing feedback on digital files. The app's interface is user-friendly, with tools readily accessible from a toolbar, and annotations save automatically to prevent data loss. Users report that the process is intuitive, allowing for quick text selection and markup, which streamlines tasks like studying or collaborative editing. For instance, a researcher can highlight key findings and attach notes for later reference, enhancing productivity on mobile devices. However, some limitations exist: reviews indicate that with PDFs larger than 100MB, performance can occasionally lag, leading to slower page rendering. Additionally, while basic features are free, advanced options may require in-app purchases, and ads in the free version can be distracting for some. Despite these minor drawbacks, Wise PDF remains a reliable choice for PDF annotation, balancing functionality with ease of use for everyday document interaction.