Will a narrated deck play on mobile without an app?

Yes, a properly hosted narrated deck plays in mobile Safari and Chrome without an app install, but there are four things to verify before sending.

First, autoplay behaviour. Mobile browsers block audio autoplay by default, so the viewer needs to tap a play control to start the deck. Make sure the play button is visible above the fold on a 375 pixel wide screen and clearly labelled. A deck that appears silent because the viewer did not see the play control is the most common cause of "broken on mobile" complaints.

Second, file size and load speed. Aim for the deck to start playing within three seconds on a 4G connection. Slides that pull in heavy background images or embedded video will tank load time. Compress images to roughly 200 KB each and lazy-load slides past the first three so the deck starts fast and the rest streams in the background.

Third, tap targets. Navigation arrows, slide indicators, and any clickable CTAs need to be at least 44 pixels in each dimension or thumbs will miss them. Test the full deck on an actual phone, not a desktop browser shrunk to a mobile width, because touch behaviour and font rendering both differ.

Fourth, the headphone case. About half of mobile viewers watch with earphones, the other half with the device speaker. Test both. A narration that sounds fine in earphones can be hard to follow on a phone speaker in a noisy environment. Add captions as a fallback so the deck stays usable on mute, which matters in offices and public transport.

If you build with voice annotations the output is mobile-ready by default. The mobile app is optional, only needed for recording on the go, not for prospects watching what you sent.