I've added a new resource to Open Education Resouces page, NetProf. You can see the languages it supports on the main page, MSA is Modern Standard Arabic. It's free and created by the Defense Language Institute and MIT.
The core of the software lets you choose a word from your target language. It then compares your pronunciation with a native speaker. The helpful part is that it breaks the word or phrase into parts. Any section where you see red is considered inaccurate. It also gives you an overall score. While this all looks very scientific, and it gives you a percentage number, consider the feedback as a general guide.
Once you create a free account and choose your language, you can then search for a word or choose from the list. First play their sample of the word, then Record just below. Note, it's a bit unusual that you hold down the Record button while you speak and then release when you're finished. You can then play your recording, play the original native speaker again, and examine your score.
On the positive site, I noticed that it found sounds that I and most non-native speakers have trouble in German. For example, the "ü" sound does not exist in English, and you can see where I had some trouble. This isn't by any means 100% accurate, though, so take it as a general guide. I have a fairly neutral U.S. accent, and I still had some red marks when comparing English.
They also have a vocabulary practice section. You need to create a New List first. Once you do so, can click the other button to Add to List. When it's time to practice, you'll see the button above for Study lists. Once you're in your list, you can either choose Learn Pronunciation or Audio Vocabulary Practice. Somewhat oddly for vocabulary practice, it shows the the translation.
There's more information under the Analysis tab, but these two parts are the most likely to be useful for language learner. I found this site via a review in FLTMag, head there for a more thorough review and comparison with Forvu, an app with a similar function.