Running a Free App Costs Your Smartphone Performance

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When given a choice, most people will download the free app over purchasing the $0.99 version any day. But free apps come with a price, and I’m not talking about data mining. Rather, William Halfond, the co-author of a recent study, wants you to consider how much that app is costing you in data consumption, battery usage, and internal memory.

For developers, the difference between a free and paid app is getting on the top of the charts, and in-app ads allow creators to get paid while getting their product out there to the people. But Halfond says, “Ads in ‘free’ apps drain your phone’s battery faster, cause it to run slower, and use more data.”

How much though? And is it enough to impact your daily smartphone use? Halfond and his colleagues have the answers.

The team of researchers did a comparison study of apps with ads and apps without to see how much of an impact the two had on battery and performance. They found that apps with ads use an average of 16 percent more energy, but some may use up to 33 percent. This increase in memory usage can lead the battery to drain faster, lowering the battery life expectancy from 2.5 to 2.1 hours on average, or to 1.7 for greedier apps. It’s no wonder the expected battery life drops so much, as researchers found ads in apps can hog 48 percent of the CPU on average.

As for data, the researchers found, on average, whenever you open an app with ads, it uses around 79 percent more network data than apps without ads, costing you around 1.7 cents each time it’s used (based on the average cost per MB charged by AT&T).

So, what does this all mean for you, the consumer? Well, Halfond and his team found that users tended to rate ad versions 0.003 stars lower on average (out of a possible five stars).

Halfond explained the findings in a press release:

“In absolute terms, this is very low, but in the crowded and competitive world of apps it’s a huge difference. It can make the difference between your app getting downloaded or going unnoticed.”

Smartphone apps are part of our future for managing everything from our daily routine to our health, and while apps are typically vetted for malicious content by Apple and sometimes Google, the ads they contain are not. An ad within a free app could point to a malicious website with malware or have a virus attached to it. Buyer beware.