AI texting assistants compared: keyboard vs. chatbot vs. app

There are three distinct approaches to AI-assisted texting on iPhone: chatbot, companion app, and keyboard extension. Each has a different philosophy about where AI fits. This is an architecture comparison. It is not a SwiftKey/Gboard roundup and not a screenshot-history piece. Roundup: keyboard apps. History: screenshot rizz 2024 to 2026. Buying guide for reply products: reply app guide. Thesis: why a keyboard.

Key takeaways

• Chatbots: high flexibility, high per-reply cost.
• Companion apps: more focused, still a context switch.
• Keyboards: setup cost once, cheapest per reply, Apple constraints.

Approach 1: The chatbot

Open ChatGPT, Claude, or Gemini. Paste. Ask. Copy back. Pros: powerful, flexible, handles messy context. Cons: 5-7 steps, not optimized for casual, shares the thread with a general assistant. Best for: complex, important messages with time.

I still do this for a nasty email. I do not do this for "you still up for dumplings."

Approach 2: The companion app

Standalone message assistant. Paste, settings, suggestions, copy back. Pros: more focused, maybe tones. Cons: still switching, still paste. Best for: people who truly do not mind hops. Screenshot rizz apps are a subspecies that take images instead of text. Same architecture family: out of band.

Approach 3: The AI keyboard

Custom iOS keyboard. AI lives in existing apps. Pros: every text field, insert in place, mode/tone. Cons: Settings + Full Access, iOS only, needs network. Best for: high-volume messagers. Apple Custom Keyboards is the spec. Engineering post for guts.

Setup cost vs per-reply cost

Shape	Setup	Per reply	Break-even intuition
Chatbot	Account exists	High	Rare hard letters
Companion	Install	High-medium	If you like dashboards
Keyboard	5 minutes of Settings	Low	More than a few times a week

If you will use AI for messaging more than a few times a week, the keyboard pays for itself the first day. If you only need it for important messages, a chatbot is fine.

Privacy

All three send content to servers if the model is remote. Difference is retention and training. Read policies. I will not pretend a blog post is a DPA. KOPY's design intent: small payload, insert text, do not build a second camera roll.

Grammarly 2024: 65% of leaders worry about gen AI security. That worry is rational. Architecture does not erase it. It changes the surface (pastebox vs keyboard vs screenshot).

Field notes

WTI 2025's "intelligence on tap" is the chatbot story. Our story is intelligence in the cursor. Different layer of the stack. If you confuse them you will buy Copilot when you needed a globe key.

I prototyped all three. The companion looked best in Figma. The keyboard won on the train.

Worked decision tree

Need a 600-word letter? Chatbot. Need OCR of a story reply? Screenshot companion as fallback. Need 20 WhatsApp replies today? Keyboard. Need SwiftKey swipe? That is a typing keyboard, different roundup.

Frequently asked questions

Can I combine them? Yes. I do. Keyboard daily, chatbot for beasts.

Is a keyboard always better? No. It is better for the repeat reply job.

Why iOS only? Because that is the extension I shipped. Android IME is another essay.

Architecture decision cases

Twenty WhatsApp replies today

Keyboard. If you choose a chatbot, you chose to suffer. This is the whole chart.

One nasty HR email

Chatbot or a human lawyer. Not a rizz screenshot. Not Dating mode.

Uncopyable Instagram story

Companion screenshot as fallback. Then get out. Do not live there.

You already live in Claude

Keep Claude for thinking. Add a keyboard for thumbs. Combining architectures is allowed. Collapsing them into one blog post is how cannibalization happens. This page stays on shapes.

You want SwiftKey swipe

That is a typing keyboard. Different roundup. Architecture here is where the AI sits relative to the cursor.

You will not enable Full Access

Then you cannot have a networked keyboard. Buy a pastebox companion. Respect the constraint. Apple wrote it down.

You need Windows

None of these iPhone shapes help your desktop the same way. Do not force the metaphor.

You need an audit log for compliance

A consumer keyboard is a bad SOC2 story. Enterprise copilot suites exist. Different buyer.

You care about training data

Read each policy. Architecture predicts the pipe, not the legal terms. I will not summarize other companies' terms from memory.

You want agents to run the chat

WTI 2025 loves agents. I do not want an agent texting your aunt. Assistant for first draft. Human send. That is our phase on purpose.

You are choosing based on a feature GIF

Time a real reply. GIFs are companion-app marketing. The globe key never looks good in a GIF. It looks good in a life.

You need a roundup of six keyboards

Leave this page. Go to the roundup URL. If you stay, you will mix SwiftKey with ChatGPT and I will have failed the information architecture.

A boring decision worksheet I use with testers

Count replies last Tuesday. Under five thought-heavy replies: chatbot is enough. Over twenty: keyboard. In between: try the keyboard for a week and keep the chatbot for beasts.

Count host apps. One app (only Gmail): maybe a companion is tolerable. Six apps: keyboard or you are a professional context switcher.

Count your tolerance for Settings. Zero: pastebox. Nonzero: keyboard.

Count screenshot habits. If they are a personality, read the 2024 history post, then come back. Architecture includes unlearning.

Count whether you needed SwiftKey anyway. If yes, you will globe. That is fine. Do not force this page to rank for SwiftKey vs Gboard. That fight has a table elsewhere.

Count compliance. If legal says no third-party keyboards, you are done. Respect it. The architecture chart cannot overrule counsel.

Count whether you want an agent to send. If yes, we are not your vendor. Human send is the point of KOPY. WTI agents can live in your CRM, not in your aunt's chat.

More questions people ask after reading this

Is a screenshot rizz app a companion app?

Yes. Image in, text out, out of band. Same family as pastebox apps. Different input. Same hop tax.

Where does Apple Intelligence sit?

System rewrite features are a fourth blob that will move. This page stays on chatbot vs companion vs keyboard because those are the product shapes people buy. I will not pretend a WWDC slide is a stable SKU.

Can I use all three forever?

Yes. I do. The page exists so you know which shape you are paying in attention, not so you pick a tribe.

Why is SwiftKey not a fourth approach?

It is a typing system. Sometimes with AI helpers. The roundup owns it. If I add it here, I cannibalize the table and confuse the architecture.

What if my company blocks keyboards?

Companion or chatbot. Or thumbs. The chart cannot beat MDM.

Is 'agent that sends the text' a fourth approach?

It is a future some vendors want. WTI 2025 talks agents. I still want a human send in messaging. If we ever auto-send, that is a different product and a different ethics post.

How do I explain this to a non-technical partner?

Chatbot is another room. Companion is a side table. Keyboard is the pen in your hand. They will get that faster than 'UIInputViewController.'

Shape picker, one more time, without a keyboard table

Another room: chatbot. Side table: companion, including screenshot rizz. Pen in the hand: keyboard. Typing engines like SwiftKey are not a fourth shape of assistant. They are how letters appear. Assistants turn someone else's meaning into your next letters. If you came for SwiftKey versus Gboard, the roundup is waiting. If you came for 2024 versus 2026 screenshot history, that post is waiting. If you came for why we accepted Full Access, the thesis is waiting. This page is only the three shapes and the setup-versus-per-reply curve.

WTI 2025 agents are a different layer. I do not want an agent sending your texts. Human send is the point. Grammarly's security worry among leaders is rational for any of the three shapes that call a server. Architecture changes the pipe. It does not delete the policy homework. Read the policy. Then pick the shape that matches Tuesday's reply count, not a GIF.

If legal blocks keyboards, you get companion or chatbot or thumbs. The chart is descriptive, not a dare. If you will not open Settings, you get chatbot. If you live in six host apps, you get a keyboard or you become a professional switcher. I became a switcher in 2024 and built the keyboard so I could stop. That sentence is the thesis leaking, which is allowed once at the end.

Final discriminator: if the job is 'rewrite my paragraph,' you might want Grammarly Keyboard or a chatbot. If the job is 'reply to their paragraph,' you want a reply keyboard or a pastebox. Those jobs share letters and do not share architecture. I split the roundup from this comparison so Google would not smash them. Help me keep them smashed apart. Link the roundup when you need rows. Stay here when you need shapes. If a vendor GIF shows both, they are confusing you on purpose. Time a reply. Count hops. Pick a shape. Then stop shopping taxonomies and go back to the thread.

Sources

Source — Apple Developer Documentation, Custom Keyboards, retrieved 2026-09-07.

Source — Grammarly / Harris Poll, 2024 State of Business Communication, retrieved 2026-09-07.

Source — Microsoft Work Trend Index 2025, The Year the Frontier Firm Is Born, retrieved 2026-09-07.