Downloadable mobile clients – fact or fiction?

We all had that joyful moment of downloading another application from the web. Some of us (well, probably a lot of us) are using Skype - a downloadable client for desktops. But what about mobile handsets? Can we have a downloadable client that truly works on a handset?

In the past year, I’ve answered RFIs and RFQs of operators and handset vendors who were seeking to develop a VoIP client. The customers asked for a client that should support the following:

1. audio calls (not a big deal).
2. video calls.
3. Large number of supplementary services.
4. They should be based on SIP - and by SIP it usually means IMS.
5. And yes - they need to be downloadable.

By downloadable, it means that the client itself is not part of the phone when you purchase it or get it from the operator, but rather an application that is later downloaded by you as a customer - either directly from the internet or from an online directory of applications that the operator has.

As an engineer in my previous life, I must say that this is a bit far fetched in my views. The main issue is the variety of handsets out there that needs to be supported and the differences between them:

1. Operating system (big one there)
2. Hardware platform
3. Baseband
4. Screen resolutions
5. Camera(s)

And the list probably goes on.

Can anyone really provide a downloadable client that supports all these cases?

Doing so requires customizing the client for virtually every handset - by rewriting the application for a different operating system, using different codecs available on the hardware platform (or better yet - optimize codecs for multiple platforms), etc.

I don’t believe that a downloadable IMS client for mobile handsets is viable with today’s technology - for me, it is fiction.

It seems that I am not alone in my views - check out what Morten Grauballe has to say about it in his post The inner secrets of the 100 million unit club.

To make a downloadable mobile client a fact, then one of the 2 should happen:

• The client should be downloadable to a limited number of devices (let’s say Apple iPhone and Nokia N95)

or

• We should wait a few years until phone platforms become standardized a bit more (through better processors and better standards - OMTP and Java come to mind).