How To Highlight And Annotate In Reading Apps?

I've tested countless epub readers for their annotation and highlighting features. My absolute favorite is 'Moon+ Reader Pro' because it lets you highlight, underline, and add notes with such ease, and even syncs them across devices. Another solid choice is 'ReadEra', which offers a clean interface and robust annotation tools without being overly complicated. For those deeply invested in academic or technical reading, 'LiquidText' is a game-changer—it allows you to create dynamic links between your highlights and notes, making it perfect for in-depth analysis. 'Google Play Books' also deserves a shoutout for its simplicity and cloud sync, though it lacks some advanced features. If you're an Apple user, 'Apple Books' integrates seamlessly with iOS and offers decent annotation capabilities, though it’s not as feature-rich as some third-party options. Each of these apps has its strengths, so your choice depends on whether you prioritize simplicity, advanced features, or cross-platform compatibility.

Reading PDFs with annotation features is something I've wrestled with a ton, honestly. My workflow got messy bouncing between a bunch of different apps for different things. I kept a few on my devices just for their specific strengths. For heavy, detailed markup, I don't think anything beats Adobe Acrobat Reader. The commenting and drawing tools are super robust, and it handles every weirdly formatted PDF I've thrown at it. But it can feel a bit 'office software' heavy, you know? It's not the smoothest for just casual reading and highlighting. That's where something like ReadEra or Moon+ Reader comes in for me. They feel more like a dedicated ebook app that happens to handle PDFs well. The highlighting is quick and simple, and organizing notes after the fact feels a bit more intuitive for book-style reading. For tablets, the game changes completely. I use an iPad, and GoodNotes or Notability are practically essential if you're working with textbooks or articles you need to mark up extensively. Writing in the margins with an Apple Pencil, drawing arrows, circling text—it feels so natural. But they're not great as a general-purpose 'library' for your PDFs; they're more like digital notebooks where you import PDFs to work on them. So my setup ended up being a hybrid: ReadEra for general reading and quick highlights, GoodNotes for deep study sessions, and Acrobat on my laptop for when I need to create or edit more formal annotations. It's a bit clunky, but it covers all the bases.

I use Kindle apps daily, and yes, they absolutely allow highlighting and annotating text. It's one of my favorite features because it makes studying or revisiting favorite passages so much easier. When I read 'The Name of the Wind', I highlighted countless quotes that resonated with me, and adding notes helped me remember why they stood out. The process is simple—just long-press on the text to highlight or tap the note icon to jot down thoughts. These annotations sync across devices, so whether I’m on my phone, tablet, or Kindle, my notes are always there. The ability to export highlights to apps like Evernote is a game-changer for organizing my reading insights.

Onyx Boox devices have their own app store, but their default Neoreader app is insane for annotations—but that's hardware. Their Android-based readers let you install any Android reading app. So if you're thinking of a dedicated e-ink device later, choose a free app now that also works on Android, so your library can transfer.

I love reading on my phone, especially PDFs for research or light novels. Highlighting in mobile reader apps is usually straightforward. Most apps like 'Adobe Acrobat Reader' or 'Xodo' have a highlighter tool in the toolbar—just tap it, select your color, and drag over the text. Some apps even let you add notes to highlights, which is super handy for studying. I personally use 'Moon+ Reader' because it syncs highlights across devices, so I can review them later on my tablet. If the app doesn’t have a built-in highlighter, try long-pressing the text to see if a menu pops up with the option. Customizing highlight colors helps me organize thoughts—yellow for key points, pink for quotes I love, and blue for references. It’s a game-changer for active reading.

Man, I bounced between so many apps before settling on ReadEra for this. It's free, which is wild because the annotation tools are surprisingly robust. You get highlighting, underlining, strikethrough, and adding text notes is straightforward. The notes are saved locally in a dedicated section, making them easy to review later. It doesn't have the deep integration with academic citation managers some might need, but for fiction readers who want to mark quotes and jot down thoughts without a subscription fee, it's a fantastic choice. The lack of major sync is the main trade-off.

You can't actually highlight or annotate text within a PDF file using the Kindle app in the same way you can with native Kindle books. The app treats most PDFs more like a static image or a document you're viewing, not as flowing, interactive text. The annotation tools just don't appear for that format. It's a pretty common frustration for readers who want to keep all their reading and notes in one place. What you can do instead is use the 'Add Note' tool, which functions more like a sticky note placed at a specific spot on the PDF page. You tap and hold on the page, and a little note icon pops up where you can type your thoughts. It's not true text highlighting, but it does let you mark a location for a comment. For serious PDF work where you need to highlight sentences or copy text, you're often better off using a dedicated PDF reader app that's built for that purpose and then maybe transferring the file back to your Kindle library later if you just want it for reading. I still keep some reference PDFs in my Kindle library for straightforward reading because I like having everything together, but I've accepted that my interaction with them there is mostly passive. The sticky-note method works okay for dropping a quick thought on a particular chart or diagram, though. It's one of those platform quirks you learn to navigate.