Quick picks by job
Pick the row that matches the PDF in your inbox.
| Your job | Best pick | Why |
|---|---|---|
| One signature, recipient uses iPhone or Mac | Apple Markup | Free and already installed |
| Free basic signing, you already use Acrobat | Adobe Fill & Sign | Free for basics |
| Lease, NDA or HR form with dates and initials | eSign PDF | Fields, flattened export, no account |
| Recipient on Windows, Android or a company system | eSign PDF | Flattened, so the signature shows everywhere |
| You need others to sign your document | DocuSign | Sending, reminders and tracking |
| You sign on Android or Windows too | Adobe or DocuSign | eSign PDF is iPhone and iPad only |
1. Apple Markup — try it first
Markup is built into Mail, Files and Photos. Tap the pen icon, tap +, then Add Signature. For a single signature going to someone on an iPhone or Mac, it's all you need, and it costs nothing.
Where it struggles: Markup adds the signature as an annotation on top of the page. Some Windows and Android viewers don't show it. It also has no real date field or checkbox tool, so long forms get slow. More in Apple Markup vs a signing app.
2. Adobe Fill & Sign — the free option in Acrobat
Adobe Acrobat Reader includes Fill & Sign for free. You can type into forms and add a signature. If you already use Acrobat, it's a sensible pick.
The trade-off is that Acrobat is a full PDF suite with paid plans, and editing, converting and cloud features push you toward an Adobe account and a subscription. See eSign PDF vs Adobe.
3. DocuSign — when you're the sender
DocuSign is the standard for sending documents out for signature, and its iPhone app is well rated. It's the right answer when you need clients or tenants to sign your document. DocuSign Personal: $11/month billed annually ($132/year), 5 envelopes/month.
If someone sent you a DocuSign link, you usually sign it free. If you only receive plain PDFs, you don't need a DocuSign plan.
4. eSign PDF — when the form is long or the recipient isn't on Apple
eSign PDF is for people who received a PDF and must sign it on iPhone. Open it from Mail or Files, draw or type your signature, add dates, initials and checkboxes, and export. Every export is flattened on the device, so the signature shows in Acrobat, Edge, Chrome and Android. There's no account and nothing is uploaded. It costs $59.99 one-time (US).
It won't edit PDF text, convert files, or send documents for others to sign.
How we compared them
We make eSign PDF, so read this with that in mind. We compared the apps on what a signer actually needs: can you open a PDF from Mail, fill dates and checkboxes, sign on every page that asks for it, and send back a file the other person can see on any device?
We left out price comparisons for apps whose pricing we couldn't confirm on the vendor's own page, and we didn't rank on feature counts. A tool with fewer features that does your job is the better pick. If your job is sending, the comparison that matters is eSign PDF vs DocuSign.
Who should not buy eSign PDF
- ✕You send contracts for others to sign — use DocuSign or a similar service.
- ✕You sign one page now and then for Apple users — Markup is free.
- ✕You're on Android or Windows.
- ✕You need a full PDF editor.
Verdict
Choose Apple Markup if
It's one signature and the other person is on Apple. Free.
Choose Adobe Fill & Sign if
You want a free option and already use Acrobat.
Choose DocuSign if
You send documents for other people to sign.
Choose eSign PDF if
You received a multi-page form, need dates and initials, or the recipient isn't on Apple. On-device, no account, $59.99 one-time (US).
FAQ
What is the best free way to sign a PDF on iPhone?+
Apple Markup. It's built into Mail and Files. Flatten the file if the recipient uses Windows or Android.
Why doesn't my signature show when I send the PDF?+
Markup saves signatures as an annotation layer that some non-Apple viewers skip. Flattening merges the signature into the page. eSign PDF flattens every export.
Do I need DocuSign to sign a PDF someone emailed me?+
No. DocuSign is for sending. You can sign a PDF attachment on your iPhone and reply with it.
Is eSign PDF a subscription?+
$59.99 one-time (US) in the US. Other plans and local prices are shown in the App Store.
Does eSign PDF work on Android?+
No. It's iPhone and iPad only.