Thinkorswim (by TDAmeritrade)

best investing apps 9 think or swim

TDAmeritrade has one of the best mobile apps among the "old guard" online investment brokerages.

The thinkorswim app is edgy and easy to use. There's a reason it has a 5-star rating in the Apple store. It's free to download. You get free trades for 60 days. Then it costs $9.99.

What makes this app really useful is all the information on it. This isn't just a place to buy and sell stocks. You can screen stocks based on P/E ratio and other factors. You can also watch news, read major headlines, set up alerts and even get some research reports.

On top of that, there's an in-app chat feature with secure text messaging so you can talk with someone ASAP if you have question. And there's a feature called Paper Money that allows you to create a play portfolio to fake trade $100,000 for awhile so you get used to trading without putting actual money at risk.

"Thinkorswim is for someone who is more opportunistic in managing their money," says Nicole Sherrod, managing director of trading. The app even offers futures and options trading, including on oil.

Thinkorswim has about 400,000 unique users a week. About 20% of trades at TD Ameritrade now occur on mobile, says Sherrod.

First published October 26, 2017: 2:33 PM ET

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