In a world where Silicon Valley's high cost of living drives talent toward the heartland, the next hot startup can come from anywhere. One city keeps turning heads: Indianapolis.

Innovation has skyrocketed since Salesforce's 2013 acquisition of Indianapolis-based ExactTarget for $2.3 billion. This massive tech exit sparked the launch of several new software startups and reinvestment of capital back into the tech ecosystem. Indianapolis has transformed from what some may have previously considered a "flyover" city into an epicenter of marketing tech. 

Digital marketing spend in the US is expected to reach $120 billion by 2021, and founders in Indianapolis are ready to meet growing demand. According to a new survey of over 350 tech leaders in the city, half of the marketing software-as-a-service companies surveyed had an estimated year-over-year revenue growth of more than 100 percent in 2017.

"Indianapolis has an advantage because there's been a couple of successful companies like ExactTarget and Angie's List that took off," said Bob Stutz, CEO of Marketing Cloud and Chief Analytics Officer at Salesforce. "In the startup market, you have to have continuous success in order for the big investors to come." 

For Indianapolis, continuous success may not be too far in the future. Here are the four trends inspiring this marketing tech hub, along with several innovative companies to keep an eye on:

1. The biggest sales and marketing channel is (still) email.

Despite the buzzworthiness of other digital channels, U.S. marketers see four times the return on email than on channels such as social media, direct media or paid search. That signals a big opportunity for tools that improve email effectiveness, and several startups in Indianapolis are taking on the challenge.

Sigstr is a software-as-a-service company that aims to maximize returns on email signatures. In 2017, it raised a $5 million Series A and announced partnerships with industry leaders Marketo, HubSpot, Oracle, and Salesforce. Indianapolis's other email marketing startups include Covideo, which offers software that enables sales teams to send personalized video inside email, and 250ok, which offers analytics software to measure email delivery, reputation, compliance, design and other metrics.

Salesforce's large presence in the city is boosting innovation around marketing tech in Indianapolis, and startups in other cities can take note that each of these fast-growing companies is tightly focused on solving one problem. By unlocking your niche, you can capitalize on a well-defined market opportunity.

2. Software that solves human problems will win.

In a world where we interact with bots almost every day, there's good momentum behind a call for real, authentic human interactions.

Just north of Indianapolis, Emplify is helping companies improve employee engagement. The platform gathers insights from employees and ties them straight to the bottom line, creating a unique tie between culture and business results.

Another Indianapolis-based startup aims to solve a different kind of human problem. Zylo's platform helps companies manage their employees' wide variety of software subscriptions, allowing them to keep what they need and ditch what they don't--and a just-announced $9 million Series A from a top Silicon Valley venture capital firm and the venture arms of Slack and Salesforce doesn't hurt.

The lesson here: It can be all too easy to get caught up in tech buzzwords. By humanizing the benefit of the technology, startups can speak to tangible problems and offer real solutions.

3. E-commerce and online sales continue to rise.

It's no secret that e-commerce sales continue to grow by billions of dollars each year, and retailers are on the lookout for ways to boost their market share.  

Indianapolis-based Viral Launch aims to help people sell more effectively on Amazon using tactics such as market intelligence, listing optimization and boosted reviews. PERQ, a tech company with an innovative play-focused company culture, helps retailers improve online engagement and measure consumer behavior by creating guided, interactive shopping experiences.

These tech companies are taking the e-commerce opportunity, which isn't unique to Indianapolis. Trends in online shopping aren't backing down anytime soon, and we can expect more innovation in the heartland as e-commerce continues to dominate retail sales.

4. Marketers value insights into customer data.

Few innovations are shaking up the marketing landscape more than customer data and artificial intelligence, and Indianapolis has a thriving ecosystem in this segment of marketing tech.

The opportunity is inspiring Indianapolis-based companies such as DemandJump, which connects marketing data with competitive intelligence to help marketers find customers faster, and recently-acquired Fizziology, which uncovers social insights and analytics in the media and entertainment space. Consulting company Lodestone Logic uses data to advise which conferences are best for startups to exhibit. Quantifi, a software-as-a-service company, lets marketers run advertising experiments across social platforms in real time.

While tech grows in cities between the coasts, small startups are going toe-to-toe with enterprise companies to compete for market share. If you move quickly, you'll be able to capitalize on these leading tech trends and be well on your way to success.