A popular iPhone app to help identify problems common to trees in Midwest and northeast U.S. states is now available for Android devices, its maker says. Purdue University says its Purdue Tree Doctor app can help homeowners, landscape professionals, arborists and garden center personnel identify more than 175 tree problems on more than 60 types of trees common to the region. "It will be like having our entire library of photos and recommendations in your pocket when trying to make a diagnosis," Purdue botany and plant pathology Professor Janna Beckerman said in a university release Friday. "Once you have a tentative diagnosis you can double-check it by following links on each photo to detailed descriptions of damage and stages of problem development," said Beckerman, who developed the app with Purdue entomologist Cliff Sadof. "From there, you can get advice to take care of the problems." The Tree Doctor app was reviewed by peers to ensure it is accurate, and it does not recommend name-brand chemicals or products to treat tree problems, Purdue said. The app is available for $1.99 in the Google Play store.