Satisfaction with Apple's iPhone is at an all-time high with 79 per cent of users saying they're 'very satisfied' with the device, compared to 72 per cent in February – or so market research group ChangeWave has found. It compared the iPhone with other makes of smartphone device, with Palm faring the worst at just 22 per cent.

Again RIM's Blackberry scored second place behind the Apple iPhone, although its 'very satisfied' rating fell one point, from 55 per cent to 54 per cent.

LG and Sanyo are tied on 40 per cent each followed by Nokia (37 per cent), Samsung and Sony Ericsson (33 per cent), Motorola (32 per cent), then Palm (22 per cent).

iPhone squeezes Blackberry

The iPhone also scored a significant win over RIM's Blackberry when it came to future mobile phone purchases. 35 per cent of ChangeWave's respondents said they'd pick an iPhone within the next three months, a 12 point climb over its previous result. That puts it ahead of the Blackberry for the first time – it scored 29 per cent, according to Fortune's Apple 2.0 blog.

The headline findings of the ChangeWave survey are backed by separate research carried out by Rubicon Consulting, which showed that 80 per cent of iPhone owners declare themselves satisfied with the device, of which over 40 per cent are 'strongly satisfied'.

The iPhone challenge

Rubicon Consulting's "The Apple iPhone: Successes and Challenges For the Mobile Industry" white paper [PDF link] also reveals that:

However the survey also reveals some significant drawbacks to owning an iPhone:

Rubicon says Apple has proved to mobile phone companies it's possible to create an entirely new business, but warns:

"Apple's type of product design is incredible difficult for most other companies to imitate, because they don't have the expertise in tying together OS, user interface, online services and hardware design. The path to success in smartphones is clear, but it's not clear how many companies have the skills to walk it."

A warning to Microsoft

Rubicon warns that Microsoft in particular faces 'severe challenges' when it comes to competing with the iPhone, and also against Google's Android. It says the company needs to decide whether it wants to be in the hardware business, the software business or both.

"Both alternatives are very high risk and require models that are outside Microsoft's core competencies. The company's recent purchase of Danger, which designed the T-Mobile Sidekick, may indicate that it intends to go down the device route."