Wall Street stock futures are mixed to lower this morning as quarterly earnings reports keep rolling in.

Shares of Apple (AAPL) are higher Tuesday, after beating expectations with its second fiscal quarter earnings report late Monday. Revenues for the quarter grew 27% from the year-earlier quarter to $58 billion.

Companies reporting today include JetBlue (JBLU), UPS (UPS) and Coach (COH) before the opening bell, and Twitter (TWTR) and Kraft Foods (KRFT) follow after the close.

Before the open, automaker Ford (F) posted a profit that missed analyst expectations as it sold fewer vehicles in North America due to the rollout of the F-150 pickup truck and continued to lose money in South America and Europe.

Today’s must-read story is by Fortune’s Roger Parloff: Smart guns: They’re ready. Are we? It looks at smart-gun technology that was designed to limit the number of children who die in gun accidents — and it’s elicited strong feelings from the pro-gun lobby. You can watch a video on the story here:

Here’s what else you need to know about.

1. Baltimore declares state of emergency.

Days of angry but peaceful protests in Baltimore over the death of Freddie Gray devolved after his funeral Monday into some of the worst riots seen in the U.S. since 1968, prompting Maryland Governor Larry Hogan to call in the National Guard.

2. Google offers an olive branch in Europe.

Google is shaking up its news service in Europe, in a move that may help beleaguered publishers, bolster its position vis-a-vis Facebook–and gain the company some allies in its battle against European Union antitrust charges. The initiative has been met with a stony silence by Rupert Murdoch’s News Corp and Germany’s Axel Springer.
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3. Twitter reports quarterly earnings.

Twitter reports its first quarter results after the market close today. One typical metric will be missing from the release this time around: timeline views. The metric, which counts each time a user logs in or refreshes their timeline, is the only standard that indicates how engaged its 288 million active users are on the site. CFO Anthony Noto has long said the metric is irrelevant given recent product changes that reduce the need to refresh social feeds. It’s unclear if Twitter will offer up a new engagement metric today.

4. Merck and Pfizer struggle against generic competition.

Merck & Co. (MRK) and Pfizer (PFE) release first quarter earnings this morning–and both are expected to post lower earnings due to rising competition from generics. Merck is also dealing with weak growth of its Januvia diabetes drug, though pay attention for any update on its potentially lucrative immuno-oncology drugs that are in clinical trials.

Meanwhile, along with rising generic competiton for its Celebrex painkiller, Pfizer is coping with the end of a longtime (and lucrative) co-promotion agreement with Amgen to sell its Enbrel arthritis drug. Investors will be more interested in updates on how its potential blockbuster Ibrance treatment for breast cancer is faring in clinical trials.

5. The Fed begins its April two-day meeting.

The Federal Open Markets Committee goes into the first of its two-day meeting on interest rate policy. Not much is expected to go down in this meeting since the FOMC already ruled out an April rate hike, but investors will be looking for more information on exactly when they might start boosting interest rates. It could be as soon as June. Look out for any word on how comfortable the Fed is getting with inflation data.

—Reuters contributed to this report.