Both apps let a tradesman send an invoice from his phone, capture a customer signature, and push the result into QuickBooks. That’s where the similarities end. Invoice ASAP has been around since 2010 and is built primarily for the solo end of field service. Billet is built for shops that send drivers out with trucks of inventory. Here’s the actual difference, feature by feature, with no marketing fluff.
Disclosure: this comparison is published by Billet and includes our own product. We’ve worked to keep it accurate and fair, but we are not a neutral third party.
The short version
Billet does what Invoice ASAP does. Mobile invoicing, a signature on the glass, sync into your accounting software. Then it keeps going: GPS welded to every signature, offline capture that survives a dead zone, proof-of-delivery documents, a counter terminal, four accounting integrations instead of two.
If you are one person with a phone and a handful of invoices a month, that extra surface is weight you do not need. If you run a crew and things get delivered, it is the whole job.
What’s in the box
| Feature | Invoice ASAP | Billet |
|---|---|---|
| Mobile signature capture | Yes | Yes |
| Per-signature GPS proof | Used for routing; per-invoice not documented | Yes, stamped on every signed PDF |
| Photo capture per invoice | Yes, unlimited | 5 / 10 / unlimited by tier |
| Offline mode | Yes (per vendor) | Built for offline; signing and sync queue work with zero signal |
| Proof of delivery as a document | Not advertised | Core product: signature, GPS, photos, timestamp on one PDF |
| Partial deliveries and back-orders | Not advertised | Yes, with linked follow-up tickets |
| Per-item rejection | Not advertised | Yes, with photos and reason codes |
| Bill of Lading | Not advertised | Yes, four variants, DOT and FMCSA compliant |
| QuickBooks Online | Two-way | Two-way |
| Xero | Direction not publicly documented | Two-way, with Quote import and tax-rate sync |
| FreshBooks | Not advertised | Two-way |
| Microsoft Dynamics 365 | Not advertised | Two-way |
| Route optimization | Not advertised | Standard tier, Google Routes API |
| Fleet GPS map | Not advertised | Standard tier, live driver positions |
| Counter / kiosk mode | Not advertised | Yes, any tablet becomes a will-call terminal |
| Card payments | Their own processing rate | Stripe Connect at Stripe’s standard rate, 0% Billet fee on top |
Feature details are summarized as of June 2026 and change. Verify current capabilities on each vendor’s own website before deciding.
Where Invoice ASAP wins
Mature in solo field service
Around fifteen years of plumbers and HVAC techs have shaped Invoice ASAP into something that fits the single-truck workflow naturally. The form fields, the recurring invoice setup, the deposit handling. It’s polished for that audience. Billet’s UX is built around someone leaving a warehouse with three deliveries in the truck, not someone diagnosing a leaky faucet.
Unlimited photos on every tier
Invoice ASAP includes unlimited photos regardless of plan. Billet meters them by tier, starting at five per ticket. If you photograph everything and you are not on a higher tier, that is a real difference.
Where Billet wins
GPS proof on every signature
This is the biggest single difference. Billet captures the device’s GPS location around the moment a customer signs, embeds it on the signed PDF, and stores it with the ticket. If a customer disputes the delivery, you have the timestamp, the GPS coordinates, and the customer’s signature on one document. Invoice ASAP uses GPS for travel-time reporting and route tracking, but per-invoice signature GPS is not a documented feature in the product.
For shops where a $4,000 boiler arrived at 8 in the morning and the customer is now telling their accountant nothing came, that single coordinate stamp is strong proof to help resolve the dispute.
Offline mode that actually works
Billet was built around the assumption that signal is going to drop. Warehouses with no cell service, customer driveways behind metal buildings, basements with one bar of LTE. Signing, photo capture, and the full sync queue all work fully offline. The queue processes the moment the device reconnects.
Proof of delivery, not just an invoice
An invoicing app proves you asked for money. A proof-of-delivery record proves the goods arrived. Billet treats that as the product: the signature, the GPS coordinates, the photos, the timestamp and the line items all land on one PDF that gets emailed to the customer and stored against the job. Partial deliveries, back-orders and per-item rejections are part of the same flow, because that is what actually happens on a truck.
FreshBooks and Microsoft Dynamics integration
Invoice ASAP integrates with QuickBooks and Xero. Billet adds FreshBooks and Microsoft Dynamics 365 Business Central, both two-way. If you’re a Dynamics shop or a FreshBooks shop, Invoice ASAP isn’t on the table at all.
Counter Mode
A lot of distribution shops have a counter where walk-in customers pick up parts. Invoice ASAP doesn’t handle that workflow. Billet has a dedicated counter device mode: a tablet sits on the counter, the office assigns a ticket, the customer signs and optionally taps a card, done.
No fee on top of your card payments
Billet takes 0% on payments. Card processing goes through your own Stripe account at Stripe’s standard rate, and Billet adds nothing to it. Check what any invoicing app clips from each transaction, because on a business doing real volume that number matters more than the subscription does.
Which to pick
Pick Invoice ASAP if
- You’re a solo operator who needs an invoicing app on your phone
- You send fewer than 50 invoices a month
- Your accounting software is QuickBooks or Xero only
- You photograph heavily and want unlimited photos on the entry plan
- You don’t need GPS proof, route optimization, fleet visibility, or a counter
Pick Billet if
- You have a team of drivers, office staff and counter clerks
- You deliver inventory rather than only service hours
- You want GPS embedded in every signature for proof of delivery
- You use FreshBooks or Microsoft Dynamics 365
- You expect to outgrow Invoice ASAP’s feature set within a year and don’t want to migrate later
The honest summary
Both are honest tools for honest work. Invoice ASAP is built for the one-truck plumber. Billet is built for the four-truck supply yard. Pick the one whose shape matches your shop, not the one that has the louder marketing.
If you’ve already got Invoice ASAP and the only thing you wish it had is signature-time GPS proof, proper offline mode, or a counter device, that is exactly the gap Billet was built to fill.
Billet launches late 2026
Billet isn’t live yet. Join the waitlist and we’ll email you the day it goes live. No account, no card, nothing to cancel.