is there any size limit of Javascript?

How is it possible that Apple thought a 24mb limit for your iCloud-sync'd Address Book was a sensible size constraint?

• Apple launched iCloud integration with AddressBook last year and imposed a 24mb limit to your address book size.  When you enable Facebook integration on the iPhone with your contacts, it adds photos.  That's awesome, but even with about 120 contacts, you will max it.  I have 2000 contacts in my addressbook.  Worse, when you hit the limit, there is no indicator, you just start seeing records stop updating, and random data loss.  Apple describes the limits only here: http://support.apple.com/kb/HT4489 There is no way Steve Jobs' addressbook would fit in 24mb, and probably not many others.  The 25,000 contact limit is amusing, because 24mb is ~25,000 kilobytes, so it's essentially saying that each contact must be under 1kilobyte in size, which is, of course, totally impossible.

• Answer:

  I think the real problem here is how Facebook is syncing contacts -- if you're maxing out your 24MB limit with only 120 contacts, the Facebook app is clearly storing contact records -- likely photos -- that are much larger than they should be or need to be -- there is no way that an individual contact record should be 200KB. Records without contact photos assigned to them can very easily be well under 1KB each, since they're otherwise entirely text-based.  In fact, the average contact record -- a name, a couple of phone numbers, an e-mail address, and a street address) comes in at around 500 bytes (~0.5KB).  Even a well-stocked contact record with several e-mail addresses, a home and work address, and Twitter, Facebook and IM accounts listed could still easily fit into 1KB.  Adding contact notes would naturally expand that somewhat, of course. What makes contact records particularly large are the photos, although iOS and the OS X Address Book do attempt to optimize added photos by resizing them appropriately.  It's unclear if this optimization occurs when inserting photos from other sources such as the Facebook app, however. For comparison, I have about 300 contacts in my Address Book, about 100 of which have photos attached.  My total address book size is slightly under 3MB.  The images are approximately 2.7MB of that.  However, in my case the photos have been added through the OS X Address Book application and/or the Contacts app on the iPhone. The average user likely has very few contacts that actually include photos -- either because they have few contacts overall (e.g. only immediately friends and family) or they have a large number of business or professional contacts that they have not taken the time to assign photos to.  2,000 contracts is not a typical use case, in my opinion, and if you're truly looking to keep that many contacts in your iOS address and assign photos to them all, it may be a fair statement that you should be looking to a solution other than iCloud, or perhaps even other than the iOS Contacts list itself.  Personally, I limit my iPhone contacts to people that I deal with on a semi-regular basis, choosing to keep professional and business contacts in a separate database.  My tactic is that if I haven't called, e-mailed or spoken to somebody in more than a couple of years, there's probably no point in keeping them in my address book.  This also decreases the chances that Siri will end up mistakenly calling some random contact instead of correctly identifying who I'm actually trying to call.