Is HTML5 usable for syncing data between devices?

Question

I work for an insurance company. They have a contact database that gets pushed to the field agents by Lotus Notes. We're trying to move away from Lotus Notes, but we first have to remove our dependency on it.

It has been suggested that a HTML5 solution could provide offline access to agent contacts and be used to sync changed from the server down and the client up.

It is my understanding that the SQL storage capabilities of HTML5 aren't fully implemented (IE and Firefox apparently don't support yet per one site I read.) LocalStorage may not be robust enough for the data we need to sync since the size limit is relatively small.

Is HTML5 a feasible solution to this issue or should we track down some kind of syncing solution? (I've been reading about one from the Ubuntu folks and Microsoft's, as well.)

Thanks!

• Darkwater23: I found this chart. It's kind of handy! caniuse.com/sql-storage
• JeffO: Is there a reason why you're creating something like this on your own? There are many products that manage contacts and distribute them to users. Salesforce comes to mind. Their next version of their mobile app should have off-line capabilities.
• Esben Skov Pedersen: Have you looked into pouchdb?

Answer 1

Check out caniuse.com. For WebSQL, it's deprecated:

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However, if key-value stores are an option that might do:

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Also check out this great listing of options.

• Robert Harvey: To be fair, all that chart says is that Microsoft and Mozilla never implemented WebSQL. Wikipedia says that the working group stopped working on the specification because nobody bothered to come up with implementations that competed with SQLite. IndexedDB does a bit better than WebSQL, if you don't mind it being buggy on a Mac.

Answer 2

In short: Your question seems to be discussed with pros and cons in the following SO posts. Look at the following references:

• Best way to synchronize local HTML5 DB (WebSQL Storage, SQLite) with a server (2 way sync)
• Offline storage - db sync
• How to synchronize HTML5 local/webStorage and server-side storage?

I would add my 2 cents with pointing to the security concern of letting collected data to remain un-encrypted in local storage. Because the way how data is collected in a device/tablet may have some personal/commercial sensitive data whose storage should comply with varies compliance rules.

• Darkwater23: Encryption is the very next requirement. The one after that is remote wiping of data. :P
• Jeffrey Sweeney: Warning from a security non-expert: Even encrypted data on the client side is at risk of being stolen. It's actually arguably easier to steal confidential data on the client's machine than data going over the wire.