Quick answer
For occasional signing, SignQuick's iOS app is the lightest option: no signer account, no desktop required, and requests are sent directly from the iPhone for $9.99/month. For teams already inside a bigger ecosystem, the DocuSign, Adobe Acrobat Sign or Dropbox Sign apps make sense — but all three still push serious workflow setup, like templates and routing rules, to desktop or web. PandaDoc's app leans toward tracking proposals rather than building them on the go.
What "digital signature app" usually means
This search covers two different needs that get lumped together. The first is someone who received a document and just needs to sign it — that almost never requires installing anything, since the signing link opens in a mobile browser. The second, and the one this guide actually addresses, is someone who wants to prepare and send a document for signature from their phone, without opening a laptop.
The apps below are compared on that second job: how much of the sending workflow actually works on mobile, versus how much still requires the desktop dashboard.
Digital signature apps compared
| App | Sender app | Signer needs app? | Free tier | Starting price |
|---|---|---|---|---|
| SignQuick | iOS app + web dashboard | No app — signs in any browser | No | $9.99/month or $99/year |
| DocuSign | iOS / Android | No app needed to sign | Trial only | From $10/month (Personal) |
| Adobe Acrobat Sign | iOS / Android (via Acrobat) | No app needed to sign | Limited, with Adobe account | From $12.99/month (Acrobat Standard) |
| Dropbox Sign | iOS / Android (via Dropbox) | No app needed to sign | Limited plan | From $15/month (Essentials) |
| PandaDoc | iOS / Android, mainly for tracking | No app needed to sign | Yes, 5 docs/month | From $19/seat/month (Starter) |
"Best for" details for each app are covered in the sections below. Pricing shown is the entry paid tier billed at each provider's standard terms — verify current pricing before buying.
DocuSign app
The DocuSign app can scan a paper document with the camera, place fields and send an envelope from a phone. It's a capable companion app, but pricing is still envelope-based regardless of device — see our full DocuSign pricing breakdown. It's the natural choice if your team already pays for a DocuSign plan and just wants mobile access to it.
Adobe Acrobat Sign / Acrobat app
Adobe's mobile app is heavier by design: it's a full PDF editor with eSignature bolted on, so it's the strongest choice if you also need to edit, convert or annotate PDFs from your phone. For pure sending-and-tracking, that extra weight is unused overhead. See Adobe Sign vs DocuSign for the full pricing comparison.
Dropbox Sign app
Dropbox Sign's mobile experience is lighter than DocuSign's or Adobe's and integrates naturally if your files already live in Dropbox. It's a solid pick for a solo sender who wants unlimited requests without a heavy interface — details in DocuSign vs Dropbox Sign.
PandaDoc app
PandaDoc's strength — building proposals with pricing tables and a content library — is a desktop task. Its mobile app is mainly useful for checking status and getting notified when a prospect opens or signs, not for authoring. See PandaDoc vs DocuSign for the full comparison.
Built mobile-first
SignQuick
SignQuick was built around the phone, not adapted to it. From the iOS app, you upload a document, add the signer's name and email or phone number, and send a unique link — the entire sending flow lives on the app, not a desktop dashboard you have to switch to. The signer doesn't need the app at all: they open the link in any mobile browser, draw their signature and confirm. Every completed signature records a timestamp, the signer's IP address and a SHA-256 hash of the document.
SignQuick has no free plan — a single subscription at $9.99/month or $99/year unlocks unlimited sends, which still works out cheaper than most alternatives on this list for a freelancer or small business signing occasionally.
Try SignQuickFrequently asked questions
Do I need to install an app to sign a document someone sent me?
Almost never. Every major eSignature service, SignQuick included, lets the recipient open the signing link in a mobile browser and sign there. The apps in this guide matter mainly for the sender, not the signer.
Which digital signature app is free?
PandaDoc offers a genuine ongoing free tier (5 documents/month). DocuSign and Dropbox Sign mainly offer time-limited trials or heavily limited free tiers. SignQuick has no free plan — it starts at $9.99/month with unlimited sends.
Can I send documents for signature directly from my phone?
Yes, with any of the apps compared here. SignQuick is built mobile-first for this specific task, while DocuSign, Adobe and Dropbox Sign apps are mobile companions to a primarily desktop/web workflow.
Is a signature made in a mobile app legally valid?
Yes. Under eIDAS in the EU and the ESIGN Act in the US, an electronic signature is not invalid simply because it was created on a phone. What matters is the audit trail behind it — timestamp, signer identity evidence and document integrity — not the device used.
Sources checked
Pricing and feature claims checked against each provider's own pages on September 15, 2026.