Seoul-built high-fidelity interaction prototyping tool — founded 2014 by Tony Kim (ex-Google), Scotty Kim (ex-Samsung) and John Song (ex-Naver) under Studio XID Korea Inc., commercial launch January 2017, $39.8M total funding including a $21M Series B in January 2025, used by 50,000+ companies in 180 countries
ProtoPie is a category-defining tool for high-fidelity interaction prototyping — sensor-driven flows, multi-screen connected experiences, smart-device and in-vehicle HMI prototypes, conditional logic, real device-data input — sitting one full step above what Figma's prototyping mode can do. The company was founded in 2014 in Seoul by Tony Kim (CEO, formerly interaction designer at Google), Scotty Kim (CTO, ex-Samsung software engineer) and John Song (ex-Naver software engineer) under the parent entity Studio XID Korea Inc.. The product entered a long beta with large-tech customers like Alibaba before its commercial launch in January 2017. ProtoPie has raised ~$39.8 million across five rounds, with the most recent being a $21M Series B closed on 22 January 2025, co-led by returning investor LB Investment and Korea Development Bank (KDB) with ~$3M committed by each. Today the tool is used by 50,000+ companies in 180 countries — disproportionately strong in automotive HMI, consumer electronics, and connected-device design. For Indian buyers the right framing is: ProtoPie is the right call for automotive (Tata Motors / Mahindra / Bajaj), IoT, smart-appliances, and advanced fintech interaction work where the prototype needs to behave like the real product. It is the wrong call when you just need clickable UI flows for a typical Indian B2B SaaS or consumer-app prototype — for that, Figma prototyping mode covers 90% of the work at a fraction of the cost.
ProtoPie is a desktop prototyping application (Mac + Windows) plus a cloud-sharing layer, focused on a narrow but deep category: high-fidelity interaction prototypes that behave like the real product, not like static screens linked together. Where Figma's prototyping mode is built around "go from screen A to screen B on tap", ProtoPie is built around variables, conditions, formulas, sensors (device tilt, sound input, camera), real-time inputs (Arduino, webhook), and component-level interactions — enabling prototypes that respond to actual device behaviour, simulate hardware buttons and dials, or stitch together multiple devices in a connected-experience demo.
The company was founded in 2014 in Seoul, South Korea by three co-founders whose backgrounds explain the product's character: Tony Kim (CEO) was an interaction designer at Google before starting the company; Scotty Kim (CTO) was a software engineer at Samsung; John Song was a software engineer at Naver, Korea's dominant search-and-portal platform. The parent legal entity is Studio XID Korea Inc., headquartered at Seocho-gu, Seoul. The product went through a long beta period with large enterprise customers — most notably Alibaba — before the commercial launch in January 2017. From the beginning the bet was that designers wanted to communicate motion, micro-interactions, conditional behaviour and sensor responsiveness to engineering, and that no existing tool let them do that at the fidelity the product needed.
Funding history: ~$3.5M Series A in July 2018 followed by additional bridge / strategic rounds, and the most recent $21M Series B on 22 January 2025 co-led by LB Investment and Korea Development Bank (KDB). Total raised across five rounds is approximately $39.8M. The Series B is being used for global expansion (Western Europe, North America), continued investment in AI-assisted prototyping and the on-premises Enterprise product, and the company's automotive-HMI vertical.
ProtoPie is now used by 50,000+ companies in 180 countries, with a customer base that skews very differently from Figma's. The biggest verticals are automotive HMI (Hyundai-Kia, Volkswagen, BMW, Toyota, plus their tier-1 suppliers), consumer electronics and smart-appliances (Samsung, LG), aerospace and industrial control, and pockets of advanced fintech and banking app design. For Indian buyers the closest-fit pockets are Tata Motors / Mahindra / Bajaj / Ola Electric on HMI, IoT / consumer-electronics startups, and the small but real pocket of Indian banks (HDFC, ICICI, Kotak) where the design team is mature enough to prototype micro-interactions at high fidelity.
True conditional logic: store values, do math, branch on them. Prototype a checkout flow that actually calculates tax. Figma's variables (added 2023) are still much shallower than what ProtoPie has shipped since launch.
Tilt, shake, microphone, camera, compass — ProtoPie pipes real device sensor data into the prototype. Critical for AR/VR/automotive/IoT design where the prototype needs to react to the physical world.
Stitch a phone, tablet, watch and dashboard into one connected prototype that talks across devices in real time. This is why automotive HMI teams use ProtoPie almost exclusively — there's no real Figma substitute.
Wire physical hardware (buttons, dials, motors) into the prototype via Arduino or web hooks. Industrial design, automotive, IoT teams use this to prototype with physical inputs before silicon is ready.
Define interaction behaviour at the component / responsive level rather than per-screen — closer to how engineers actually build. Reduces designer-to-engineer translation loss substantially.
Cloud-sharing layer for stakeholder review and the ProtoPie Connect runtime which lets prototypes ingest live data via OSC, MIDI, Arduino, plugins, webhooks. The Connect surface is what unlocks the truly hardware-coupled use cases.
Important pricing correction: earlier versions of this review listed "Starter $13/month" — that tier no longer exists in 2026 and was inaccurate even when it ran. ProtoPie's actual pricing is materially higher and reflects the tool's specialist positioning. Live rates from protopie.io/plans:
For Indian buyers, all tiers are billed in USD with 18% IGST applicable. The Pro tier at $67/editor/month converts to roughly ₹5,700/editor/month all-in — close to 9x the page's previous "₹1,092/month" claim. For a 5-designer Indian automotive HMI team on Pro the annual cost is approximately 5 × $67 × 12 × 1.18 ≈ $4,750 / ₹4 lakh per year; an Enterprise contract for a 20-designer Tata-Motors-scale team can run ₹15–30 lakh per year all-in.
ProtoPie is the wrong call when: you only need clickable UI flows for a typical Indian B2B SaaS or consumer-app prototype (use Figma); you're a solo designer or pre-Series-A team on a budget (Figma + Origami / Principle / Lottie covers most of what you actually need at zero cost); you're producing rapid lo-fi flows for stakeholder feedback (use Figma or even Whimsical / FigJam); or you don't have an in-house interaction designer who can actually wield ProtoPie's variables-and-conditions model.