Y Combinator Summer 2021 (S21) Companies

Nomod is a payment links platform that enables businesses to send payment requests via WhatsApp and accept payments through multiple methods including buy-now-pay-later, mobile wallets, and major cards. The platform serves businesses in the UAE with same-day payout capabilities and integration options for e-commerce and web platforms.

3 investors

Novatr delivers online cohort-based courses for architects, engineers, and designers seeking to develop professional skills, with instructors from major firms like Autodesk, BIG, and Google. Students work collaboratively on live projects in small groups and graduate into positions at architecture, construction, and real estate firms across 45+ countries.

2 investors

Odwen provides warehouse location discovery and reservation services for businesses across multiple sectors, enabling them to find, book, and monitor warehouse space in tier-1, tier-2, and remote locations in India.

4 investors

Odys designs and builds long-range, hybrid-electric VTOL aircraft for defense, logistics, and civil applications. The company's aircraft use flap-based thrust vectoring architecture and serve missions including tactical cargo transport, emergency medical evacuation, and defense operations.

5 investors

Okani offers a subscription-based healthcare service in Mexico that provides digital primary care through chat and app-based consultations, then coordinates access to secondary care from physicians, labs, pharmacies, and clinics for patients who typically pay out-of-pocket for medical services.

1 investor

Onebrief develops software designed for military and defense organizations, enabling real-time collaboration and knowledge access for command and operational teams. The product integrates processes with real-time updates for defense and government use cases.

12 investors

OneSchema provides AI-powered data integration and validation automation for enterprise data operations teams. The platform automates data intake, extraction, mapping, transformation, and validation across multiple file formats and enterprise systems using LLM-based AI agents.

2 investors

OneShop is a multi-channel listing tool that enables sellers to cross-post inventory across multiple resale and marketplace platforms including Poshmark, Mercari, Depop, eBay, Etsy, and Facebook Marketplace.

1 investor

OneStopKitchen provides AI-powered software for restaurant inventory, operations, and logistics, and operates shared kitchen facilities in high-traffic urban areas where restaurants can expand their operations without upfront costs. The platform enables customers to order from multiple cuisines in a single transaction via dine-in, pickup, or delivery.

1 investor

Onfolk provides payroll and HR management software for growing UK teams, consolidating employee data, time-off tracking, and accounting integrations in a single platform. Founded by former Monzo engineers, the company aims to replace manual spreadsheet-based processes and fragmented tools with an integrated system that handles payroll runs and employee onboarding at scale.

1 investor

Onsite provides digital pricebook software for HVAC distributors, replacing traditional Excel and PDF catalogs to help dealers access product details, find equipment matchups, apply incentives, and generate proposals.

1 investor

Openlayer provides a platform for testing, monitoring, and managing AI models across the development and production lifecycle. The platform serves AI-driven teams ranging from startups to enterprises seeking reliable and trustworthy AI system deployment.

8 investors

Opkit offers AI-powered telephone agents that handle administrative tasks like patient intake, benefits verification, and scheduling for medical practices and telehealth providers. The service is built to HIPAA and SOC 2 specifications.

1 investor

Orderli provides tableside ordering software for European bars and pubs, allowing customers to order via QR code without an app while giving staff visibility into orders and kitchen operations. The platform uses predictive analytics to help venue owners optimize inventory and menu decisions.

1 investor

Outloud.ai records and analyzes customer conversations at drive-thru windows to help restaurant operators identify upselling opportunities and inventory issues in real time.

2 investors

Output builds generative AI models trained on biological data to discover and develop medicines. The company focuses on applying large biological models to improve diagnosis, treatment, and disease prevention.

4 investors

Pactima provides a platform serving businesses of various sizes, offering flexible solutions with emphasis on service and security.

1 investor

Palette is a platform for sales leaders and managers to set short-term goals, track performance, and motivate teams through personalized incentives and coaching programs. It integrates with CRM systems like Salesforce to provide real-time performance data and leaderboards.

1 investor

Palla provides APIs and white-label solutions for fintech companies and financial institutions to enable peer-to-peer payments and cross-border transfers in seconds across 180+ countries. The platform offers instant transfers 24/7 with built-in security and compliance features.

5 investors

Pandai develops a mobile learning application with curriculum-aligned quizzes and practice exercises for secondary school students in Southeast Asia, designed to improve test performance and identify knowledge gaps.

1 investor

Parallel Bio develops human immune organoids and computational tools to predict drug efficacy across diverse patient populations, replacing animal testing in drug discovery. The company aims to accelerate pharmaceutical development and reduce clinical trial failure rates through human-first biological prediction models.

9 investors

Patterns provides an AI-powered platform for financial analysis and reporting that allows users to perform data analysis using natural language instead of traditional spreadsheets. The system uses large language models and autonomous query capabilities to enable financial professionals to conduct complex analytical work through conversational interfaces.

2 investors

Payflow is a financial wellness platform for employers that enables employees to access earned wages on demand instantly and provides flexible compensation benefits through a mobile app and card. The platform serves companies looking to improve employee retention and reduce payroll processing costs.

10 investors

Payhippo offers fast lending to small businesses across Africa, with particular focus on Nigeria.

3 investors