How to Add a Signature to a Photo, Plus Your Phone Number

How to add a signature to a product photo, plus your phone number

To add a signature to a photo, iPhone has an Add Signature button in Markup, and on Android you use the Pen in Google Photos. For a phone number on a whole set of photos, stamp the text on all of them in one batch.

A signature and a phone number do two different jobs on a product photo

As of October 2026, the Photos app on iPhone and Google Photos on Android can both add handwritten strokes and text to a photo. Before you start, separate the two jobs. A signature tells viewers whose photo it is. A phone number gives customers a way to reach you when the photo gets shared somewhere else.

So keep the signature small and in a corner, like an artist's signature. The phone number needs to be bigger and clearer, because customers have to read it right away on a phone screen. Putting both in the same corner makes the photo look cluttered.

On iPhone, Markup has a built-in Add Signature button

Apple's support page on signatures says you can use Markup to add your signature to images in supported apps such as Photos and Notes. The steps:

1. Open the photo and tap the Markup icon.
2. In the Markup toolbar, tap the plus button, then tap Add Signature.
3. Tap a saved signature, or sign a new one with your finger and tap Done.
4. Drag the signature to a corner. Drag any blue dot on its box to resize it.

Your iPhone saves the signature after the first time, so next time you just tap it. You can create several signatures, such as a nickname or your initials. Apple suggests turning your iPhone sideways to get more room to sign.

The phone number uses a different button in the same toolbar. According to Apple's Markup page, you tap the plus button, choose Add Text, type the number, then change the font, size and color with the tools below.

On Android, sign with the Pen and type the number with Text in Google Photos

Google Photos has no dedicated signature button, but it has a Pen you can sign with. The Google Photos help page explains: open the photo, tap Edit, then Markup. If you do not see it, go to Edit, Tools, then Markup.

Tap Pen to sign with your finger in a corner of the photo. Tap Text to type your phone number, and touch and hold the text box to drag it somewhere else. When you finish, tap the checkmark, then Save as copy so the original photo stays untouched.

A finger signature often comes out thin. Sign larger than you need, then place it in a corner with a plain background so it stands out.

Stamp a phone number on a whole set of photos at once with iLoveIMG

Editing photos one by one only works for a few. The iLoveIMG Watermark IMAGE tool stamps the same line of text on many JPG, PNG or GIF images in one go, right in your browser.

Click Select images, pick the whole set, then click ADD TEXT and type your number. The toolbar at the top has font, font size, bold and italic, background color, text color, alignment and transparency. The text is white by default, so add a dark background behind it when the photo is bright.

If you have your signature as a PNG file with a transparent background, click ADD IMAGE to stamp it in the same batch. According to the iLoveIMG pricing page, the free plan watermarks 30 images per task. The Premium plan raises that to 120 images, for $7 a month, or $4 a month billed annually ($48 a year), per the pricing page as read on Oct 19, 2026.

How should you write a phone number on a photo so it is easy to read?

Split the number into groups, such as 555 123 4567, so the eye reads it faster than a long run of digits. Put the contact channel first, such as WhatsApp, Text or Call, so customers know whether to call or message.

Make the text large enough to read on a phone, not just on the computer screen you edit on. Put the number along the bottom edge, where the product rarely sits. Check every digit before you stamp the whole batch, because one wrong digit means redoing all of them.

Five common mistakes when you add a signature and a phone number to photos

White text on a bright background. The text almost disappears. Add a dark background behind it, or switch the text to a dark color.

A signature over the product. Viewers see the signature before the item. Move it to an empty corner and make it smaller.

Saving over the original. On Android, choose Save as copy so you keep the original to edit again.

Text cut off after posting. A square photo posted in a vertical or horizontal frame can lose the corner with your number. Check social media aspect ratios: 4:5, 1:1, 16:9 and 9:16 before you add text.

A font that lacks your characters. Accented letters such as é or ñ can show up as empty boxes if the font does not include them. Test the font on one photo first. See 6 common mistakes when adding text to photos for more.

For a few photos, adding a signature right on your phone is enough. For a whole set that needs the same phone number, stamp the text in one batch.

If your product photos also need headline text, a highlight color and matching badges, read How to Add Text to a Photo on Your Phone or Computer. To run headline text and badges on a whole folder at once, see the headline text and brand badge skill.

Sources, accessed Oct 9, 2026 (iLoveIMG pricing re-checked Oct 19, 2026):

• Apple: Fill out forms, sign documents, and create signatures on iPhone
• Apple: Add text, shapes, stickers, and more with Markup on iPhone
• Google Photos Help: Edit your photos (Android)
• iLoveIMG: Watermark IMAGE and Pricing plans
• Illustrative photos: Unsplash (Aleksei Ezhkov, Signature Pro, V H), Unsplash License.

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