If data from a mobile marketing firm is to be believed, we could be in for a slew of new iPad models when the range is refreshed this Spring.

Apple is testing four new models of iPad in and around its Cupertino headquarters, according to mobile marketing company Fiksu (via TechCrunch). This squares with previous rumours suggesting Apple will unveil a slew of new tablet models in the Spring.

However, just because four new devices are in testing it doesn't necessarily mean we'll see four new iPads. Fiksu says it monitored four new models being tested ahead of the launch of the last two iPad Pros. So expect somewhere between two and four new models in the coming weeks.

Fiksu can track these devices using its tracking and attribution SDK (software development kit). Apple test runs apps on new models of iPad ahead of their announcement, some of which inevitably include Fiksu's tracking tech.

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All of the devices it detected were being tested in and around Cupertino, where Apple is based.

So which models are they? Sadly there's no way of knowing. But, as ever, there have been plenty of rumours concerning the new tablets.

KGI Securities analyst - and noted Apple speculator - Ming-Chi Kuo predicts we'll see a refreshed 12.9in iPad Pro, a new 10in or 10.5in model with a narrower bezel, and a wallet-friendly 9.7in version.

The two bigger models are expected to feature the A10X chip, which is a version of the same processor found inside the iPhone 7. The budget model is thought to sport the A9 chip found in the iPhone 6S.

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