Apple and Samsung saw their market shares drop by 4.8 and 2.6 percentage points to 22.3 and 17.6 percent over the cited period, respectively, according to Strategy Analytics.
In contract, unbranded, low-priced White Box tablet PCs took the top spot in the market in the July-September period with a 29.9 percent share.
The market researcher forecast that global tablet sales will reach 247.7 million units this year, up 8.9 percent from last year, and rise further to 291.4 million units next year, up 17.6 percent from 2014.