As earnings season continues, the first few days of May have already featured plenty of volatility as companies share their latest quarterly updates. Three notable companies that made big moves this week include tech giant Apple (AAPL 0.58%), on-demand virtual appointment health platform Teladoc (TDOC -2.37%), and electric-car company Tesla (TSLA 4.76%):

  • Apple's growth accelerated as the tech giant beat analyst expectations.
  • Teladoc posted triple-digit revenue growth as members and visits soared.
  • Tesla's widest-ever quarterly loss seems to have spooked some investors.

Here's a closer look at each of these stories.

iPhone X, Apple Watch, and Airpods charging on Apple's AirPower mat

Image source: Apple.

Apple's impressive second quarter

In Apple's second quarter of fiscal 2018, the iPhone maker posted revenue and earnings per share of $61.1 billion and $2.73, up 16% and 30% year over year, respectively, and ahead of consensus analyst estimates for the two key metrics. Highlighting Apple's momentum, both metrics saw accelerated growth compared to recent results; in the company's fiscal first quarter, revenue and earnings per share increased 13% and 16% year over year, respectively. Momentum in Apple's year-over-year revenue growth is particularly strong, accelerating for six quarters straight. 

Best of all, Apple's business saw broad-based growth across product segments and geographies. iPhone revenue increased 14%, services revenue climbed 31%, and wearables revenue jumped 50% year over year. Further, Apple posted year-over-year revenue growth in every geographic segment, with both Greater China and Japan seeing more than 20% growth.

Apple stock jumped about 5% after its second-quarter earnings report was released.

Teladoc's surging growth

On-demand virtual appointment platform company Teladoc posted impressive first-quarter revenue of $89.6 million, up 109% year over year and above management's guidance for revenue between $86 million and $88 million. The company's revenue growth was fueled by a 41% year-over-year increase in paid memberships and 57% growth in total visits. An impressive 606,000 people received virtual care during the quarter.

Importantly, Teladoc's adjusted earnings before interest, taxes, depreciation, and amortization (EBITDA) improved significantly on a year-over-year basis; adjusted EBITDA was $1.4 million, up from a loss of $9.1 million in the first quarter of 2017.

Teladoc's guidance many have impressed investors, as management said it expected second-quarter revenue to be between $86 million and $87 million. On average, analysts were expecting second-quarter revenue of $84 million. 

Teladoc stock jumped about 6% on Wednesday, following the company's first-quarter earnings release after market close on Tuesday. 

Tesla's massive loss

Concerns about Tesla's ongoing Model 3 production ramp-up mounted this week after the company said it lost a whopping $710 million during the quarter -- worse than its $675 million loss in the fourth quarter of 2017 and more than double the $330 million loss Tesla posted in the year-ago quarter. Tesla's $710 million net loss attributable to common stockholders translated to a worst-ever loss per share of $4.19. On a non-GAAP basis, Tesla lost $3.35 per share. 

Of course, Tesla's record first-quarter vehicle deliveries helped drive a 26% year-over-year increase in revenue. Revenue growth was also helped by a big boost in Tesla's energy storage sales. Energy storage deployments increased 161% sequentially as Tesla continues to target a three-fold increase in energy storage megawatt-hours deployed this year compared to last year.

Tesla stock fell about 8% on Thursday as investors seem less confident in the automaker's ability to ramp-up Model 3 production and curb losses.