iPhone 5 big success, but no leap forward analysts

The new iPhone 5 is on its way to unprecedented commercial success, but the world's most iconic smartphone is facing tougher competition from rivals out-innovating Apple, analysts say.

Apple's newest iPhone launched Friday has a host of design and technology improvements: it is lighter, slimmer, faster and more powerful, and has improved

Enderle said the new iPhone is "the most elegant smartphone" on the market, but that its design targets only segments of the market. That contrasts with Samsung, which offers a range of devices from entry-level to high-end.

For Apple to have just a single

"Apple's failure to continually bring new device innovations to the market allows competitors to catch up and threaten its iOS platform.

"Today, Apple's iOS platform and ecosystem seem invincible. But all empires eventually crumble, and unless Apple ups its device innovation game, we may be seeing Apple's iOS empire approaching its zenith."

Apple has fierce customer loyalty and has been gaining users, but has failed to keep pace with smartphones powered by Google's Android operating system.

Research firm IDC says Apple has 16.9 percent of the global smartphone market, with 68 percent of the market held by makers of Android phones, led by Samsung.

Ramon Llamas, mobile analyst at IDC, agreed that Apple is "just catching up to the trend" in many areas, but is not ready to bet against the Cupertino, California firm.

"Apple is still the reigning champion," Llamas said, noting that Apple has kept its customer base with a broad "ecosystem" that includes its huge app store and iTunes platform.

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