"Do you even vape, bro?" In California, the answer is increasingly, "Yes."

Vaping is an alternative to smoking that involves inhaling vapor from an electronic device. Between 2015 and 2016, sales of marijuana oil cartridges, which are used for vaping, soared 400% among customers who use delivery service Eaze, dubbed the "Uber for weed."

Vaporizers' explosive growth may be a key driver in the falling sales of marijuana flower, the fluffy, green stuff you smoke, according to Eaze's second annual "State of Cannabis" report.

The report, released February 8, explores trends in consumer demographics and buying behaviors. Eaze, which operates in California only, used data from 250,000 users on its platform and surveyed 5,000 customers, making it one of the state's biggest reports on marijuana spending yet.

Two big caveats: People who buy pot using an online delivery service might not be representative of the entire market, and the report also does not reflect consumer habits outside California.

The survey found that in December 2015, marijuana oil cartridges accounted for 6% of Eaze's total sales. In December 2016, the category shot to 24%.

Plus, one in five orders placed on Eaze included a vaporizer cartridge in 2016.

On the flip side, marijuana flower sales fell from 75% of Eaze's total sales in 2015 to 54% in 2016. However, flower remained the most popular product on the platform last year.

Marijuana flower is the fluffy, green stuff you smoke. Lucy Nicholson/Reuters

The rise of vaporizers comes at a time when the legal weed industry is attracting top talent from Silicon Valley, driving innovation in the category. There's now a range of devices to fit every consumer's needs, whether they prioritize ease of use, portability, style, smart design, or cost.

One of the most popular new devices, the Pax 3, has been called the "iPhone of vaporizers" for being on par with Apple's high standards of design. The brushed aluminum body features clean lines and sensors in the mouthpiece that activate the device. It retails for $274 online.

With help from the ever-growing vape market, marijuana sales could top $20 billion by 2020.