Last week, Y Combinator held its Summer 2025 Demo Day, presenting a new class of more than 160 emerging startups.
Much like recent cohorts, most companies introduced AI-focused innovations. Yet, there was a noticeable shift: rather than simply labeling products as “AI-powered,” numerous startups are now crafting AI agents or building the foundational tools and infrastructure for them. This group featured a surge in voice AI platforms and new ventures aiming to help others tap into the “AI economy” using advertising and marketing solutions.
We connected with several investors who focus on YC startups to discover which companies they found most compelling and which drew the most investor attention.
Here are the startups that were named most frequently:
Autumn
What it does: Stripe-style payments for AI startups
Why it’s a fave: AI startups often rely on intricate payment models, mixing flat-rate subscriptions, usage-based fees, credits, and optional extras. Managing these complex billing schemes with Stripe usually requires time-consuming manual work. Autumn addresses this with open-source infrastructure that streamlines Stripe integration for AI companies. Their solution is reportedly already in use by hundreds of AI applications and 40 YC startups. With Stripe leading digital payments and the AI sector booming, a billing platform tailored for AI could become the next big thing in fintech.
Dedalus Labs
What it does: Builds a Vercel-like platform for AI agent deployment
Why it’s a fave: Just as Vercel streamlines startup hosting and deployment for developers, Dedalus Labs claims its platform automates key infrastructure for AI agent creation, reducing complicated coding work to just a few clicks. The company manages advanced needs like autoscaling and load balancing, which it claims makes launching agents both fast and straightforward.
Design Arena
What it does: crowdsources ratings for AI-generated design aesthetics
Why it’s a fave: With AI capable of producing a vast array of designs quickly, a new challenge arises: determining which creations are actually worthwhile. Design Arena addresses this by crowd-ranking visuals produced by AI, generating real-world feedback that urges models to improve. Major AI labs recognize the value in training their models for higher-quality output, and some are already among Design Arena’s clients.
Getasap Asia
What it does: Technology-driven distributor for Southeast Asian retailers
Why it’s a fave: Getasap Asia was started by Raghav Arora at the age of 14, just three years ago. The company leverages technology to deliver goods to local shops, eateries, and large supermarkets across Southeast Asia in under eight hours, and has already generated millions in revenue. According to its website, General Catalyst has invested in Getasap Asia, and sources indicate the company’s valuation was one of the highest in this YC cohort.
Keystone
What it does: AI-powered engineer that repairs production bugs
Why it’s a fave: Founded by Pablo Hansen, who earned his AI master’s degree at 20, Keystone aims to minimize software failures. Their AI system detects and resolves bugs for clients like Lovable and has already turned down a seven-figure acquisition proposal, according to Hansen.
RealRoots
What it does: AI-based friend-matching service for women
Why it’s a fave: While dating apps are plentiful, RealRoots focuses on addressing social isolation in a different way. Their AI matchmaker, Lisa, interviews women and arranges group activities that connect users with compatible new friends. Although the AI’s conversational role might be limited, RealRoots’ model is showing traction: last month, the company reported $782,000 in revenue from 9,000 paying users.
Solva
What it does: Uses AI to automate insurance claim workflows
Why it’s a fave: Solva’s AI platform automates time-consuming duties for insurance professionals, from completing detailed claims to avoiding incorrect payments. Within just ten weeks of launching, Solva secured $245,000 in annual recurring revenue (ARR), sparking significant investor interest.
Perseus Defense
What it does: Miniature missiles to neutralize drones
Why it’s a fave: With reports of China deploying large numbers of affordable drones, the U.S. military urgently needs budget-friendly counter-drone options. Perseus is developing compact missiles engineered to bring down drones at a much lower price than existing systems. Various U.S. military branches have already requested demonstrations from Perseus, which could pave the way for major contracts.
Pingo AI
What it does: AI-driven language learning tutor
Why it’s a fave: While apps like Duolingo have popularized language learning, many still lack regular conversation practice, which is key to fluency. Pingo addresses this gap by enabling users to converse with its AI, which emulates a native speaker. This innovative method is catching on quickly, with the team reporting 70% monthly user growth and $250,000 in monthly revenue.
