CoThinkAI
The AI-Assisted Group Chat That Remembers and Grows With You
One shared AI for your people. It learns naturally from your conversations, and anything you pin becomes lasting context it always remembers. Smarter decisions, together.
Access the best models from every major provider
What makes CoThinkAI different
AI that actually remembers what matters
Most AI chats silently forget. CoThinkAI is built so they don't.
The problem with every other AI chat
Traditional solo AI chat apps send your entire conversation with every message. As chats grow, the AI silently decides what to keep and what to drop. Important details vanish without warning.
Priority context you control
Pin the facts that matter — “Mom is allergic to shellfish,” “budget is $3k” — and set a system prompt per room. These are always injected into every AI response as top-priority context, never compressed or dropped.
Auto-summarized, never bloated
As conversations grow, CoThinkAI automatically compresses older messages into smart summaries behind the scenes. Your chat stays lean and fast — the AI gets truths, summaries, and recent messages instead of a bloated wall of text.
The Problem
You're the AI middleman.
It's exhausting.
You research something on ChatGPT. Screenshot the answer. Text it to your partner. They have a follow-up. You go back to ChatGPT. Repeat. Forever.
CoThinkAI puts everyone in the same AI conversation from the start. No screenshots. No copy-paste. No being the middleman.
The old way
The CoThinkAI way
Group Chat
Your whole group, one AI conversation
Everyone in the room sees the same thread. Ask questions, brainstorm, debate options — the AI responds to your whole group like a helpful teammate who never sleeps.
Permanent Memory
Heart it once. The AI remembers forever.
Tap any message to pin it as a “truth” — allergies, budgets, preferences, schedules. The AI carries these facts in every response, so you never re-explain context.
Like pinning a note to the fridge, but the AI actually reads it.
Bookshelf Project
We only have a table saw and a drill
Pinned by Dan
Max board length from the store is 8ft
Pinned by Shannon
Mid-century style, hardwood, tapered legs
Pinned by Dan
Budget is $200 for materials
Pinned by Shannon
Heart any message — the AI always remembers.
Graduation Banquet
Venue max capacity is 120 people
Grandma needs a wheelchair-accessible table
Mom is allergic to shellfish
Catering deposit due by March 28
Car Diagnostics
2019 Honda CR-V, 68k miles
Clicking noise when turning left
Brakes done in January
How It Works
Tap a message. Pin what matters.
Tap any message to open it in focus mode. Pin the entire message, or highlight just the part you want the AI to remember.
Option 1: Pin the whole message
Select text to pin a specific part, or pin the whole message.
For a mid-century bookshelf, I'd suggest tapered legs and walnut veneer plywood. You can get a full sheet of walnut ply at the store for about $55. With your table saw, you can rip the shelves and sides from one sheet.
Option 2: Pin just a selection
Select text to pin a specific part, or pin the whole message.
For a mid-century bookshelf, I'd suggest tapered legs and walnut veneer plywood. You can get a full sheet of walnut ply at the store for about $55. With your table saw, you can rip the shelves and sides from one sheet.
Option 3: Add from the Lens tab
Facts the AI always remembers.
We only have a table saw and a drill
DanMax board length is 8ft
ShannonEveryday questions
GPT-5.4 Nano
OpenAI
Gemini 3.1 Flash
DeepSeek V4 Flash
DeepSeek
GPT-5.4 Mini
OpenAI
Deep research & writing
Claude Sonnet 4.6
Anthropic
GPT-5.4
OpenAI
Grok 4.20
xAI
DeepSeek V4 Pro
DeepSeek
The absolute best
GPT-5.5
OpenAI
Claude Opus 4.7
Anthropic
Gemini 3.1 Pro
Model Freedom
Dabble in every AI. Commit to none.
The AI industry wants you to pick a team. We don't. Switch between GPT, Claude, Gemini, Grok, and DeepSeek — per room, anytime. Fast model for quick answers, frontier model when it matters.
One subscription instead of three. The lineup updates as providers ship new models, so you're always on the latest.
Value
Three subscriptions? Or one?
ChatGPT Plus costs $20/mo for GPT only. Claude Pro costs $20/mo for Claude only. That's $60/mo just to compare two providers. CoThinkAI gives you access to all major models for a single flat price — and your whole group shares the plan.
Only the room owner pays. Everyone else joins free.
Separate subscriptions
CoThinkAI Pro
Built Smart
A quick word about tokens
Every AI message uses “tokens” — tiny chunks of text the AI reads and writes. More tokens = slower, less efficient chats. Here's why CoThinkAI is fundamentally smarter about this.
What are tokens?
Tokens are fragments of text (~¾ of a word). Every time you message an AI, it reads your tokens in, thinks, and sends tokens back. Both directions use resources.
The waste problem
Most AI apps send your ENTIRE conversation history with every single message. 200 messages deep? The AI re-reads all 200. That's ~50,000 tokens per message.
How CoThinkAI fixes it
We automatically compress older messages into smart summaries. The AI gets: system prompt + pinned truths + summary + recent messages. Just ~4,000 tokens total.
You save automatically
You don't configure anything. As conversations grow, CoThinkAI handles compression behind the scenes. Longer chats. Fewer tokens. Smarter AI.
Other AI apps (300 messages deep)
Full history re-sent every single time
CoThinkAI (300 messages deep)
Smart summary + recent messages + pinned truths
92%
fewer tokens per message
Longer conversations. Fewer tokens. Smarter AI.
500+ messages compressed into a single summary. Nothing lost, everything optimized.
Pro Tips
4 ways CoThinkAI saves tokens without you trying
Pin your truths
Instead of re-stating “Mom is allergic to shellfish” every conversation, pin it once. Saves ~50 tokens per re-statement, per message, forever.
Use the right model
Quick question about dinner? Use a Fast model (pennies). Deep research on your renovation? Switch to Powerful. Match the model to the task.
Rolling summaries work automatically
As your conversation grows, CoThinkAI compresses older messages into smart summaries. You never think about it — it just keeps working.
Pause AI when you don't need it
Having a conversation that's just between humans? Toggle AI off. Zero tokens used. Toggle back on when you need help. Keep your conversation lean — no unnecessary AI replies cluttering the thread or eating into your context window.
Customizable
One AI, infinite personalities
Each room has its own system prompt. Turn the AI into a trip planner, a recipe helper, a homework tutor, or a budget advisor. Your “Meal Prep” room gets a cooking expert. Your “Vacation” room gets a travel guide.
Tweak the personality anytime from the Lens tab.
Live Sync
Real-time, always in sync
Messages appear instantly for everyone. Typing indicators show who's active. Unread badges tell you what you missed. Jump into any conversation and pick up where your group left off.
Like iMessage, but with AI superpowers.
Human Mode
Sometimes you just want to talk to each other
One tap mutes the AI for your messages. Have a quick sidebar with your partner, then flip AI back on when you need help. The AI catches up on what it missed.
Pricing
Simple pricing. No token anxiety.
Flat monthly plans. No credits, no per-message billing, no surprise charges. Only the room owner pays — members join free.
Free
Try CoThinkAI
- 3 rooms, 3 members each
- 50 AI messages per day
- Fast models (GPT-5.4 Nano, Gemini Flash, DeepSeek)
- 5 image uploads per day
- Rolling summaries & Pinned Truths
Plus
For families & couples
- 10 rooms, 15 members each
- 200 AI messages per day
- Powerful models (Claude Sonnet 4.6, GPT-5.4, Grok 4.20)
- Automatic live web search
- 50 image uploads per day
Pro
For power users & large groups
- Unlimited rooms*, 30 members each
- Unlimited AI messages
- Frontier models (Claude Opus 4.7, GPT-5.5, Gemini 3.1 Pro)
- 50 Frontier messages per day
- Unlimited image uploads
No credit card required.
*Unlimited plans are subject to reasonable use. Soft limits may apply to prevent abuse.
Who is CoThinkAI for?
Anyone who lives, plans, or dreams with other people.
Couples
Coordinate meals, budgets, travel, and life decisions. No more copy-pasting AI answers in your texts.
Example rooms: Meal Prep, Vacation 2026, Budget, Date Night Ideas
Families
Plan trips, manage household logistics, help with homework. One shared AI brain for the whole family.
Example rooms: Family Trip, School Help, Gift Lists, Holiday Plans
Friend Groups
Plan events, brainstorm adventures, coordinate group decisions. AI helps everyone, not just the organizer.
Example rooms: Bachelor Party, Book Club, Game Night, Group Trip
AI Explorers
Try every major AI model without juggling subscriptions. GPT, Claude, Gemini, Grok, DeepSeek — all in one app.
Example rooms: Model Playground, Research, Writing Lab
The Non-Technical
If AI feels intimidating, CoThinkAI makes it as simple as texting. No jargon, no command line, no learning curve.
Example rooms: Dinner Tonight, Weekend Plans, Travel Ideas
Small Teams
Brainstorm, research, and problem-solve in dedicated rooms. Each room gets its own AI personality.
Example rooms: Brainstorm, Research Sprint, Project Alpha
Frequently asked questions
How is this different from ChatGPT/Claude?
Those are solo AI tools — one person, one conversation. Worse, they silently lose context as chats grow. The AI decides on its own what to keep and what to forget, so important details vanish without warning. CoThinkAI is built differently: your whole group shares one thread, and you control what the AI remembers. Pinned truths and system prompts are always folded into every response as top-priority context. As the conversation grows, rolling summaries compress older messages automatically — so the AI stays sharp without dropping the things that matter.
Do my family/friends need their own subscription?
No! Only the room owner needs a plan. Everyone you invite chats for free.
What AI models are available?
Models from OpenAI (GPT-5.4, GPT-5.5), Anthropic (Claude Sonnet 4.6, Claude Opus 4.7), Google (Gemini 3.1), xAI (Grok 4.20), DeepSeek, and more. Switch models per room. We refresh the lineup as providers ship new models, so every tier stays current.
What are tokens and should I worry about them?
Tokens are how AI measures text (roughly ¾ of a word). CoThinkAI handles token optimization automatically behind the scenes — rolling summaries, smart context compression, pinned truths. You get flat monthly pricing with no per-token charges.
Is my conversation data private?
Yes. Your conversations are stored securely in your rooms, protected by row-level security. We don’t train on your data or share it with third parties.
Can I use CoThinkAI alone?
Absolutely! Many people create personal rooms for different topics. The multi-model access and pinned truths are great even if you’re the only one in the room. But it really shines when you invite your people.
What happens to my conversations if I cancel?
Your messages aren’t deleted. You can always read your history. Your plan downgrades to Free, which keeps 3 rooms with Fast models.
Do you keep the AI models up to date?
Yes! We’re constantly updating every tier with the latest models as they’re released. When OpenAI, Anthropic, Google, or any provider ships a new model, we add it to the appropriate tier so you always have access to the best available — no action required on your part.
Ready to think together?
Create your first room in seconds. Invite your people. Let the best AI models in the world help your group get things done.
No credit card required.