YC Winter 2009 (W09) companies

Airbnb connects travelers to short-term accommodations listed by private hosts, covering everything from spare rooms to entire homes and villas. Hosts list their spaces to paying guests who would otherwise book hotels or traditional rentals. The platform replaces both the hotel booking process for travelers and the vacancy problem for property owners with unused space.

Cloudkick builds a management and monitoring platform for cloud servers running on providers such as Amazon EC2 and Rackspace Cloud. DevOps and infrastructure teams use it to track server health, receive alerts, and organize deployments across cloud environments. It replaces manual server oversight and ad-hoc tooling with a unified dashboard and automated alerting.

Divvyshot builds a photo-sharing platform for consumers who want to exchange full-resolution images with friends. It replaces the quality compromises of older sharing tools by letting users send and receive photos at their original resolution, without degradation.

Echodio built a music library sync and streaming service for consumers. It let users keep a single music collection accessible across multiple devices and players, and stream that library to a home media center. The product replaced the manual work of copying and managing music files across separate devices. The company was acquired in 2009.

Foodoro connects consumers with small-batch, artisanal food producers through a direct-to-buyer marketplace. Shoppers can discover and purchase specialty food products that are otherwise hard to find outside a maker's local area. The platform replaces the informal, word-of-mouth process buyers previously relied on to track down independent food makers and their goods.

Heyzap built a mobile ad network serving app developers on Android and iOS. It provided advertising, publishing, mediation, and cross-promotion tools that replaced fragmented, manual efforts to monetize and distribute apps. Both large publishers and independent developers used the platform to reach new users and generate revenue from their existing audiences.

Nambii builds a location-aware dating service, delivered through iPhone apps, that lets singles discover and flirt with other users nearby. It replaces the cold-start problem of traditional online dating by surfacing matches based on physical proximity in real time.

PetaSales builds B2B sales tooling for businesses seeking to manage and accelerate their sales processes. The product targets sales teams that otherwise rely on manual outreach and tracking across disconnected tools.

Picurio builds a web-based platform for consumers to store, organize, and share photos. It replaces desktop photo management software and fragmented manual file organization with a centralized online tool accessible from any browser.

Recurious builds a community-driven music discovery platform where listeners vote on indie tracks using a daily allotment of hearts. Songs rise or fall based on collective taste, replacing editorial gatekeepers and algorithmic recommendations with peer curation. Listeners earn reputation points, level up, and unlock badges, turning passive listening into a progression system.

reMail builds a mobile email app that downloads a user's full email archive directly to the iPhone, enabling fast, comprehensive search across all messages without relying on a server. It replaces the slow, incomplete search built into standard mobile email clients. Google acquired reMail in February 2010.

Skysheet builds a browser-based spreadsheet tool for business users, delivering spreadsheet functionality directly in the web browser without requiring locally installed software. It targets the productivity work that desktop spreadsheet applications traditionally handle.

Spaces Life builds tools for the real estate and construction industry. No website content or program description is available, so specific details about the product, target customer, or workflow it replaces cannot be established.

Volantio builds Vector, an agentic AI platform that helps airlines turn mismatches between passenger demand and available capacity into incremental revenue and lower operating costs. Airline revenue and operations teams deploy specialized AI agents that continuously scan the post-booking passenger journey, identify oversell, demand, and reallocation opportunities, and execute targeted moves automatically within the airline's existing systems. The platform replaces manual monitoring and slow, ad-hoc intervention by revenue and capacity teams at carriers including Qantas, Emirates, Alaska Airlines, and Iberia.

Voxli delivers group voice chat for gamers and teams entirely inside a browser, supporting up to 200 simultaneous participants. Each chat room lives at a persistent URL that members share via email or instant message, replacing the need to install or administer a dedicated voice server. A push-to-talk mode extends the experience outside the browser on Windows and Mac.

Wattvision sells energy monitoring software for homeowners and residential landlords, connecting to existing submeters from EKM Metering or Rainforest Automation to deliver live consumption data updated every ten seconds. For rental property owners, it replaces manual meter reads and spreadsheet billing by generating accurate PDF utility bills from real meter readings, applying flat or time-of-use rates, fees, and credits automatically. Tenants receive bills via a shareable link without needing an account.