Google has added Google Now to its Google Search app for iOS. This provides local traffic information, weather data and more. Unfortunately, this also keeps GPS on permanently on an iOS device, depleting its battery.
After installing the new Google Search app, I had noticed that my iPhone's Location Services icon was on permanently. I quit all apps that could be using GPS or location services, but it was still visible. I restarted the phone, and it was still visible. It turns out that it was Google Now, and I resolved the issue by deleting the Google Search app.
You can also just turn off Google Now, in the Google Search app's settings. (See this screenshot by Dave Hamilton.) If you want to use Google Now, be aware that it will drain your battery, and remember to turn it off when you don't need it.
I assume Google will update the app soon to fix this, but in the meantime, it's a good idea to be aware of this issue.
Update, June 1: As you can see below in the comments, a Google representative claimed that Google Now has no effect on iOS device battery life. Interestingly, this person posted the exact same content on dozens, perhaps hundreds of websites that were claiming this was in issue. The Loop published an article with a screenshot for a recent update, whose notes discuss improving battery life. But The Loop's Jim Dalrymple, in an update to the post, says he might be wrong.
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