The traditional pet industry, valued at $60 billion in the U.S., is getting a makeover. Technological advances make it even easier for local businesses involved in pet sitting, grooming, walking, training, and boarding to reach customers, streamline processes, and scale their operations.

Why it's hot: Forty percent of customers in the pet care industry are ages 30-49. Millennials are aging into this group and getting more pets than previous generations. According to research firm Mintel, three-fourths of American 30-somethings have dogs, compared with half of the overall population. Meanwhile, more than half of Americans in their 30s have cats, compared with 35 percent of the overall population. Millennials with pets also expect to use technology to buy services, providing opportunity for new ventures in e-commerce, subscription packages, and connected devices like pet wearables.

What's required: An affinity for animals is, of course, a must. But you'll also need some behavioral training skills and an ability to market yourself to continue gaining new customers. To integrate technology into your processes, you'll need a level of proficiency in building apps and websites or the ability to work with an expert.

Barriers to entry: Depending on the business, barriers to entry can be quite low. Pet walking and sitting might require very little upfront investment, but boarding, grooming, and training will require capital for facilities, equipment, and health and safety certifications.

The downside: Customer turnover can happen quickly in the pet services industry, and it might take some time to build up a loyal base. The nature of the business might also require long hours and an always-on-call customer service policy. You'll often need to be available on weekends and holidays, when pet owners might be traveling.

Competition: The industry hasn't seen much consolidation apart from a few grooming franchises like Wag N Wash and Best Friend's Choice Whiskers & Paws. When it comes to sitting, boarding, walking, and grooming, the most competition is likely to come from small, independent local players. In the more tech-heavy segments of the industry, startups like pet toy and treat subscription service BarkBox, services platform Rover, direct-to-consumer pet pharmaceutical company Vets First Choice, and smart-collar maker Whistle Labs are some of the dominant companies.

Growth: Pet grooming and boarding revenue was nearly $8 billion in the U.S. in 2016, and IBISWorld projects 7 percent annual growth through 2021. According to CB Insights, between 2012 and 2016, $486 million was invested in the global pet tech sector across 172 venture capital deals. The worldwide pet wearables market alone will be a $2.6 billion market by 2019, market research firm IDTechEx predicts.