One of the best applications for the Blackberry platform is the Blackberry Messenger application.  It allows Blackberry users to message each other using their device’s unique PIN number.  The messages come and go quickly and no SMS messages are used in the process.

This sort of feature is sorely missed on the iPhone OS.  That is until now.

Whatsapp Messenger is a messaging client for the iPhone OS that allows iPhone users to communicate directly with each other.  They key is only iPhone users can use the application.

Best of all the application supports push notifications so even though it’s closed you’ll still be alerted when one of your contacts sends a message.  You can also set the app to notify you via push when one of your contact’s changes their status.

Each user can set a custom status message and assign it to themselves.  Although I didn’t use this feature you also have the option of syncing your WhatsApp status to your Facebook status as well.

This makes seeing what each of your contacts is up to quite easy.

You can then choose which method to use to contact them, chat right in the app, e-mail, phone etc.

If you choose to chat right in the app itself you’ll bring up a threaded chat window that has a customizable wallpaper background.

The app works internationally as well so you can communicate via chat with your friends all over the globe without using SMS or minutes.

I’ve been playing with the application all morning and so far I’m finding it works quite well.

Other than missing a voicemail tab you could possibly use WhatsApp in place of the default phone application on the iPhone.  Which of course begs the question, how did Apple let it into the App Store?  Doesn’t that replicate something that the iPhone already does?

I had one hiccup during set up which the developer quickly addressed for me.  The application uses your iPhone’s phone number to identify you and your friends.  This number must be set using the “mobile” tag in each contact you wish to use with the app. in your address book.  If it’s set using the “iPhone” tag the application won’t recognize it.  This bug has apparently been corrected in the upcoming next release of the application.

My other wish is that they’d make it possible to add contacts via e-mail not only phone number.  To be honest there are some contacts that I don’t wish to share my telephone number with but am more than happy to give up my e-mail address to.  I asked the developer about this and it seems there’s no plans at present to make this possible.

Whatsapp is free in the iTunes App Store, so check it out today and start chatting.

Thanks to @Shangraham and @Alli_Flowers on Twitter for pointing this app. out to me.

Related posts:

1. Expanded Push Email Headed For iPhone 2.0
2. Gpush offers Gmail push on the iPhone (if approved)
3. Prowl – the way push e-mail on the iPhone should be
4. VR+ Voice Messenger Updated for iPhone
5. GPush for iPhone brings push Gmail – sorta