Selected work
Four projects across mobile, web, AI and websites. The results are in our clients' own words.
BillSend
An invoice maker for iPhone. Make an invoice in under a minute, send it by email, text or link, and get paid. Clients don't need the app.
Who it's for
People who do the work: carpenters, electricians, gardeners, photographers, cleaners, cafés and shops.
How clients pay
Card, Apple Pay or bank transfer mark an invoice paid on their own. PayPal and Venmo go to the owner's email, then they tap Mark paid.
What's in it
- Estimates that turn into invoices
- Deposits and recurring invoices
- Read receipts and invoice history
- Receipts, expenses and tax-year reports
- Client signatures on estimates
SineMax Films
A rebuilt website and booking platform, delivered in under three weeks.
“Sentinel completely rebuilt our website and booking platform in under 3 weeks. The speed and quality blew us away—our inquiries doubled within a month.”SineMax Films · Film Production Company
AstraMD
An AI-powered patient intake chatbot, built with healthcare compliance in mind from day one.
“They built us an AI-powered patient intake chatbot that cut our admin workload by 40%. The team understood healthcare compliance from day one.”AstraMD · Healthcare Platform
Royal Montessori
A new school website that loads in under two seconds.
“Professional, fast, and they actually listen. Our new site loads in under 2 seconds and parent inquiries are up 60% since launch.”Royal Montessori · Education
Ready to Start Your Project?
We'll send a free written estimate within 48 hours of our first call.