If you needed any more evidence that Twitter’s business has rapidly turned mobile, just follow the money.

The company reported today that almost 9 out of every 10 advertising dollars it brings in are earned on mobile devices, mainly phones. Actually, Twitter said in its quarterly report today that 86 percent of its ad revenues come from mobile, and that almost all of its revenues come from advertising. The rest — usually a few percentage points — comes from licensing historical tweet data through Gnip.

Actually, the high proportion of mobile revenue isn’t terribly new. Last quarter, 88 percent of Twitter’s revenue came from mobile. But at the time the company went public back in 2013, mobile constituted only 65 percent of revenues (interestingly, 75 percent of Twitter users were mobile at the time of the IPO).

In general, Twitter sells advertisers in-feed promoted tweets, promoted trends, and promoted accounts.

Twitter has been doing a lot of work to expand the capabilities and reach of those products. It launched auto-play video, as Facebook has done. It expanded its self-service ad platform to 200 countries around the world. It enhanced its Twitter Audience Platform to include new targeting methods and content formats.

In May, Twitter bought the assets of retargeting company TellApart for $22.6 million. Twitter will use the people and technology to bring retargeting capabilities to advertisers on mobile platforms.

Unfortunately, all this work doesn’t seem to be moving the needle for investors. Twitter’s stock dove 10 points in after-hours trading after it announced Q3 earnings on Tuesday.