Online therapy has been growing in popularity, as have apps for tackling emotional health concerns and promoting wellness. Sites like Breakthrough.com and Virtual Therapy Connect use videoconferencing to allow therapists to counsel patients remotely; mobile apps like Personal Zen enable users to play games on their own, to reduce stress.

Now, a start-up called Lantern aims to combine mobile and online tools with remote nudging from a professional to help users tackle troubles like anxiety, sleep problems and poor body image. The service links users with licensed therapists who check in with their clients, initially by telephone and then via secure electronic messaging.

Alejandro Foung, chief executive and co-founder of Lantern, described it as a middle-ground between buying a self-help book and paying $100 or more for an hour of in-person therapy. Users pay $49 a month or $300 a year. “It’s an easy, efficient way to learn evidence-based tools,” Mr. Foung said. Users can try a variety of techniques and continue to use those that work best for them.

They complete an online assessment that asks questions about their worries, moods, eating and sleep habits, then register for a 15-minute phone call with their assigned therapist. They then receive audio-guided exercises and tools daily, which they complete at their own pace. The tools are based on principles of cognitive behavioral therapy, an approach that emphasizes the connection between thoughts and behaviors and often involves self-help techniques. Someone who is feeling anxious might be directed to practice deep breathing techniques, or to try five minutes of progressive muscle relaxation, which involves tensing and relaxing muscle groups. Therapists, whom Lantern calls coaches, check in with users electronically to monitor progress and offer encouragement.