Generative Fill on iPhone: How to Add or Replace Anything
Use generative fill on your iPhone: paint an area, type a prompt and let AI add or replace objects. How it works, prompt tips and realistic examples.
By Ayoub Farid · · 2 min read
"Generative fill" became famous on desktop editors: select an area, type what you want, and AI paints it in. You can do the same thing on your iPhone now — no laptop needed.
What generative fill does
Generative fill fills a selected area of a photo with new content based on a text prompt. It can:
- Replace an object (a cup → a donut)
- Add something to an empty spot (an empty table → a vase of flowers)
- Change part of a scene (a grey sky → a sunset)
Unlike a sticker, the result is generated to match the photo's lighting, perspective and focus.
Generative fill on iPhone with Erase Spark
In Erase Spark the feature is called Replace Object:
- Pick a photo.
- Brush over the area you want to change — or an empty spot where you want something added.
- Type a prompt, such as "a cozy armchair".
- Generate, compare before and after, and save.
Prompt formula
A simple formula works well:
object + one detail + optional style
- "a vase + of yellow tulips"
- "a golden retriever + puppy sitting"
- "a hot air balloon + red and white"
Keep it to one clear sentence. More words don't mean better results.
Mask size matters
The painted area controls where the new object appears and roughly how big it is. Want a tall plant? Paint a tall area. Want a small cup? Paint a small one. If the result is cut off or squeezed, paint a bit larger and try again.
Realistic uses
| Goal | Example prompt |
|---|---|
| Fill a gap after erasing someone | "an empty wooden bench" |
| Stage a room photo | "a green potted plant" |
| Fun social post | "turn it into a giant donut" |
| Fix a dull sky | "a blue sky with soft clouds" |
| Product mockup props | "a sprig of eucalyptus" |
For 25 more ideas, see how to replace objects in photos with AI.
Be honest with generated content
Fun edits are fine. But don't use generative fill to misrepresent things that matter — the condition of a product you're selling, features of a property, or events in the news. More on that in our guide to photo editing ethics.
Try it on your own photos
Erase Spark brings generative fill to iPhone and iPad as Replace Object, alongside AI erase and one-tap background removal. Free to download.
Frequently asked questions
Can you use generative fill on iPhone?
Yes. Apps like Erase Spark let you brush an area and type a prompt to fill it with new AI-generated content.
What is the difference between generative fill and object removal?
Object removal fills an area with background. Generative fill fills it with something you describe.
How do I write a good generative fill prompt?
Name the object first, add one detail like color or material, and keep it to one sentence.
Why does the generated object look the wrong size?
The painted area sets the size. Paint an area closer to the size you want and try again.