More than half, or 58 percent, of the total 56 billion smartphone app downloads expected this year will be Android apps, while Apple iOS will account for 33 percent.
Microsoft's Windows Phone will have a share of slightly less than 4 percent and BlackBerry will see 3 percent, ABI Research said in a statement Monday.
iOS will lead the apps market in tablets, though, accounting for 75 percent of the estimated 14 billion tablet app downloads this year. Android tablet apps will make up 17 percent, excluding those downloaded by Amazon's Kindle Fire. Downloads to Amazon's tablets will take up 4 percent, while Windows-based tablet apps will see 2 percent, the market research firm said.
ABI Research said it expects a growing number of smartphone-focused developers to adopt an Android-first strategy within the year.
ABI Research senior analyst Aapo Markkanen said: "[This means the] most pressing issue for Google is how much of the handset momentum will trickle down to tablets, where Apple is holding the fort remarkably well."
He noted there is an upside to the Android fragmentation issue since Google can actually benefit from Amazon's tablet push. The Kindle Fire will add much "critical code mass" to positioning Android as a platform for tablet apps, he explained.
ABI Research's estimates of smartphone app downloads corroborates with another report by IDC, which stated more smartphones than feature phones will be shipped in 2013 worldwide for the first time. Handset makers would ship about 918.6 million smartphones, making up 50.1 percent of total mobile shipments globally.
IDC attributed the shift largely to emerging economies. It said smartphone demand had been burgeoning in China, Brazil and India, as these economies had grown, creating a larger middle class prepared to buy smartphones.