What are some examples where offline works for a web app? It seems like the utility is really niched so I don't understand why they make this default. None of the things I've made would make sense using offline (completely anecdotal but still).
That said, offline-friendly app caching with Service Workers is extremely useful, and changed the way I see and make web apps.
Now when I use a web app that isn't offline-friendly, I get annoyed. Always demanding a live internet connection obviously creates latency and unreliability for apps.
I changed a former client's app to be offline-friendly with Service Workers, and the benefit was obvious: their app now loaded immediately for repeat users, and they could access much of their data even when they were offline (on a flight, on a crappy Wi-Fi, etc etc).
I made a side-project to help my band members share and edit chord/lyrics sheets (also using Web Audio to give karaoke-style chord playback!) and again I made sure to set up full Service Worker caching. I also used PouchDB for the user data, which was beautiful: I didn't need to run any database server (we just used Cloudant's free instances), all our songs were synced into local browser storage (in real-time when online), and most importantly, the whole app worked perfectly while in the basement rehearsal space that completely blocks mobile signals.
(I'm not working on it nowadays. It's up on https://sketch.band and the code is at https://github.com/mbrock/sketchband under AGPL3. If you wanna try it, the undocumented syntax for the song is: each line should look like "C Dm7 / Once upon a time you dressed so fine".)
Basically offline-first technologies really help make the web into a good platform for apps.
In dashboard application, I store data in browser and notify users about last sync time: http://wstaw.org/m/2017/05/19/dashboard.livechatinc.com-iPho...
Tons of web apps that work in offline mode, which we had since a decade or so -- from games to utility apps.
>It seems like the utility is really niche
Hardly.
For an e-commerce website, this might be the user's shopping cart and favorites. For a note taking app, this might be the last note the user edited. For a Twitter client, this might be the user's drafts and the last 100 tweets on their timeline. This way, the app can say "you're offline, but you can still look at some of this data and do things with it, and we'll sync you up when you get back online".
Native apps already do this. E.g, try posting a picture to Instagram while you're offline.