Shimpi expects Apple to continue to tailor chips to balance application performance and battery life on smartphones and tablets. A6 is based on the existing ARMv7 architecture and has a new floating point core, he said.

"Apple knows exactly what they want to do. They can deliver performance when they know they have applications that need it," Shimpi said.

Apple is committed to increasing performance but is very particular about battery life, even if it has to lower the clock speed of a CPU, said Linley Gwennap, founder and principal analyst at The Linley Group, which analyzes and benchmarks chip performance. Based on certain chip parameters, The Linley Group earlier this week also said it thought the A6 has a custom CPU.

"I wouldn't be surprised if they put [A6] in the iPad," Gwennap said. Apple could just crank up the clock speed and put it in the iPad to take advantage of the larger battery in the tablet.

It's possible that Apple will ultimately design a custom ARM-based CPU for Mac laptops, but will perhaps wait two years for ARM's 64-bit architecture, Gwennap said. ARM processors are currently 32-bit and cannot address more than 4GB of memory, while Mac laptops need 64-bit architecture and the capability to address more memory. ARM has already announced the ARMv8 64-bit architecture and expects devices like smartphones and tablets based on the architecture to start shipping in 2014.