The number of malicious apps stood at 718,000 for Q2.
A report by Trend Micro has revealed that the number of malicious and high-risk Android apps will exceed one million by the end of 2013.
According to the report, the number of malicious apps for the second quarter stood at 718,000, up 40% from 509,000 in the first quarter.
Online banking malware increased 29% to 146,000 infections in Q2, when compared to 113,000 attacks in Q1.
The US was the top target of malware, taking up 28% of one million instances, followed by Brazil with 22% and Australia with 5%.
Trend Micro found that methods for selling malware toolkits have evolved, with sophisticated malicious tools being sold through inexpensive, free or special offers.
Trend Micro VP of technology and solutions JD Sherry said due to the fractured nature of the Android network, it is difficult for patches to reach users in an effective timeframe.
"In some cases, users will never get patches as vendors leave their customers at risk of attack," he said.
"Until we have the same urgency to protect mobile devices as we have for protecting PCs, this very real threat will continue to grow rapidly.
"At the rate this malware is accelerating – almost exponentially – we appear to be reaching a critical mass. To fight this, Android users need to take great care when using their devices and take the simple, but effective, step of adding security software to all mobile devices."