Unfortunately, it is not the Blockchain for iOS wallet app, but instead just their block explorer utility.  [Update: Apparently, the real deal -- full wallet.]

There does seem to be a way to activate the full wallet functionality.
It is best to install it ASAP.

http://itunes.apple.com/gb/app/blockchain/id493253309?mt=8&ls=1

Hmmmm, not from the way that piuk describes the operation of the blockchain.info wallets. They appear to be a fairly ingenious method of securing online wallets (private key is generated, stored and encrypted locally, then signatures are used to access the funds. Not sure how they validate the signatures! But it seems to work)

The code is open source.
Please feel free to take a look for insecurities:

https://github.com/blockchain/My-Wallet-iPhone

Yes, that's what tin-foil Carlton was concerned about, the open source aspect.

I do understand that this has not done the Satoshi client any harm (far from it), but I have a good idea of how many developers are throwing their collective nous at that project (and also a good impression of their calibre as coders). Plus there's plenty of other evidence about the extent to which others disseminate and analyse the source.

With blockchain.info wallet, piuk appears to be the sole developer. Not trying to cast any aspersions against piuk, he appears to have done a great job judging by the feedback in the main thread, but I'm still not quite confident enough to use the app. I will be sitting back and waiting for the moment, as there's no compelling use case for me (yet)

Other than that its great for just monitoring funds in another wallet.

That attack won't work with the app store, the signatures would fail.

As far as downloading a malicious version the same advice goes for any other bitcoin software, just make you you download it from a trusted source.  You could easily download a recompiled version of the mainline bitcoin client that was modified.  Just be vigilant.

hmmm, unable to download... Might be because i have the app from Cydia too, lol.

Nice to know.

Some questions remains:

Who checks the signatures? How often?

That is necessary for many things since Apple has designed the iOS system with large restrictions on what they can do compared with things like Android, Bada, Tizen, Meego. Those four are based on Linux, which is free and open software.