iPad design this spring

If history is any guide, the iPad may be due for an update in March or April, Piper Jaffray says.

Gene Munster, an analyst at the firm, today noted that Apple has averaged four months between events since 2009, and it has tended to update its tablet in the spring. While Apple just updated the iPad in October when it introduced the iPad Mini, it may unveil new iPad body styles similar to the smaller tablet, Munster said.

He added that it's unlikely Apple will introduce an iPad Mini with Retina display given current iPad Mini supply constraints.

Another area that could be updated is the Apple TV with better software and an early take at an App Store. Munster noted he expects to see an Apple TV update in the next six months if Apple plans to launch a television by the end of the year, which he said is likely.

"All in, if Apple does have a spring event this year, it may not result in significant new products, but we believe the pipeline for the rest of the year, including a cheaper phone and a television, will excite investors about Apple's ability to innovate," Munster said.

Apple has long led the market with its tablets and phones, but it has come under more pressure lately. Rivals, specifically Samsung, have gained traction in key product categories, and worries have emerged that Apple's falling behind in innovating. Most of the company's major product launches have started to occur in the fall, which means a major update to phones and tablets may not happen for a while.