As the week wrapped up, data shows the US economy expanded at the fastest annual growth rate in almost four years.
The world’s biggest economy grew at an annual rate of 4.1% in the second quarter, the fastest rate among industrialised nations, the US Commerce Department said.
Twitter shares plunged over 18% after the social network warned it could potentially lose millions of users as it cleans up the platform.
The slump came despite a record profit for Twitter in a quarterly report which also said the number of users could fall as part of the effort to weed out abusive and fake accounts.
“Twitter has provided yet another knockback for the tech-focused Nasdaq index, with the social media platform following Facebook lower,” said market analyst Joshua Mahoney at IG.
The Nasdaq was down 0.7% in late morning trading in New York.
Facebook on Thursday warned of weaker growth, sending its shares falling nearly 20% and wiping out some $100bn in market value.
Investors have been concerned about the financial impact of greater EU privacy protections, which many major internet firms are applying to all their users, as well as greater public concern about misuse of their data.
European shares closed with higher gains. London finished 0.5% higher, with shares in telecoms group BT rising more than 5% after posting better-than-expected first-quarter earnings.
Paris climbed 0.6% while Frankfurt added 0.4% in value, aided partly by this week’s easing in EU-US trade tensions.
Asian stocks mostly edged higher Friday with Tokyo buoyed once more by a weaker yen, which helps exporters.