The Features Every Social Trading App Needs (And How They're Built)
TL;DR
- Social trading apps have converged on six features: verified trader profiles, a live trade feed, copy/trade-from-feed mechanics, chat and comments, moderation, and live video.
- Build the trading side yourself: performance calculations, sharing permissions, order execution, and every compliance decision have to work even if the social layer is down.
- Buy the social infrastructure (feeds, chat, moderation, video) and keep the thin conversion layer that turns your trade events into activities as your own code.
- Sequence it as profiles + feed first, comments and moderation together, then copy trading and video as their own projects with their own review.
Building a social trading app is a tough needle to thread. Effectively, you are building two different types of app: the social side requires what any social app needs, which is profiles people want to follow, a feed to scroll, chat to keep people talking, and moderation that keeps it safe. The trading side needs to follow the rules and be exact, with orders filled, real numbers in real time, and every action recorded for auditors.
But they can't feel separate. The social side needs to layer on top of the trading to complement it. When someone makes a trade, the people following them should see it straight away, be able to talk about it, and, if they like the look of it, make the same trade themselves.
For that, we see six features that the top social trading platforms have all built in some form: verified trader profiles, a live feed of real trades, a way to trade or copy straight from that feed, chat, moderation, and live video. Let's go through each one: what you need to build for the feature, and what you can buy to get the right functionality for your users.
1. Verified Profiles Give People a Reason to Trust a Trader
The reason anyone follows a trader is that they believe the numbers. On X, that's a leap of faith, because anyone can post a screenshot of a winning trade (after adding a few zeros with Inspect). Inside a brokerage app, it should never be. The broker knows exactly what happened in the account, and the profile should show it.
Real-world example:
Take Robinhood Social. Every profile belongs to a customer who's been through KYC, and it shows their P&L for the day and the year, their profit rate, and their past trades, all verified live. The user agreement spells out exactly what a profile can show, down to the fill price and what share of the portfolio each position was.
(source: Robinhood)
There are two kinds of data on each profile:
- The handle, avatar, and bio, which the user writes themselves and can change whenever they like.
- The return, P&L, profit rate, and drawdown, which come from a performance service. That service reads the ledger, works the numbers out on a schedule, and publishes a summary that says how it calculated them, what window they cover, and when they were last updated. The profile shows that summary, and there's no way to edit it from the profile.
Verified only means something if the calculation is right. Say an account goes from $10,000 to $15,000, but $5,000 of that was a deposit. The trader didn't make 50%. So pick time-weighted or money-weighted, use the same one for everyone, and say which one on the profile.
The KYC documents never leave the identity service. All the community database gets is a flag that says this person is verified, and a reference to the account that doesn't mean anything on its own.
In Stream, this all sits on the user object. Your backend creates each user with the server-side API, using the same account ID you use internally, and the KYC documents stay in your identity service. The performance service then writes the profile numbers onto that user as custom fields (return, the window it covers, the method, and when it was last updated) along with a verified flag.
Feeds, Chat, and Video all read the same user record, so a profile card, a comment, and a live session show the same numbers without another call to your backend. Update these fields through Stream's server-side API, and disable the client-side "Update Own User" permission to prevent users from modifying their own profile data.
2. A Live Feed of Real Trades Gives People a Reason to Open the App Every Day
The feed is where the community lives. For a social trading app, that means trades should come into it straight from the order system. Someone typing "bought NVDA. To the moon, Jensen." is just a post. The same trade landing in the feed the moment it fills, with the real price and size, is what people open the app for.
Real-world example:
NAGA's For You feed mixes activity on the assets you hold, posts about your watchlist, and what the community is talking about, ranked by relevance, and every trade post links straight to the order ticket.
(Source: NAGA)
Say a trader with 40,000 followers closes an options position and has opted in to sharing:
- The OMS records the fill. The execution report has the account ID and the whole order in it, so it can't go out as it is.
- The fill and an outbox row are written in one transaction, so the feed never shows a trade the database rolled back.
- A service in between turns it into an activity. It checks what the user agreed to share, drops the private fields, and stamps it with the execution time, the publish time, and a version.
- The feed service sends it to the 40,000 followers, to the contract's feed, and to anyone who asked to be told when this trader closes something. Connected phones get it over the WebSocket, and the rest catch up when they reconnect.
By step one, the trading system has done its job. The feed can fall behind or go down, and the order is still filled. Opting out goes back through the same pipeline and pulls the activities out of every feed that has a copy.
In Stream, that conversion step is yours, and everything after it is Feeds. You set up feed groups for user timelines, following, one per instrument (the exact stock or options contract), and notifications, with For You as a ranked feed on top, and the follow graph, fan-out, comments, reactions, and WebSocket delivery are handled for you.
3. Trading and Copying From the Feed Lets People Act on What They See
"Trade from this post," "Duplicate," and "Copy this trader" all look like three versions of the same thing. They're not. Each one signs the user up for something different.
| Interaction | What the user agrees to | What's underneath |
|---|---|---|
| Trade from a post | One order, entered by hand | A normal order ticket that knows which post it came from |
| Duplicate a position | One order, prefilled from someone else's, checked before sending | Look up the instrument, get a fresh quote, then the normal ticket |
| Copy a trader | An ongoing instruction to copy their future trades | A stored copy relationship, a sizing engine, and reconciliation |
Real-world example:
eToro does all three of the above. Duplicate opens a ticket with the contract filled in and a warning that the price may have moved, and CopyTrader mirrors a trader's whole portfolio, stop-loss changes included, with a Copy Stop-Loss over the lot.
(Source: Wikitoro)
The post someone taps might be a week old, and the account might not even be approved for the instrument. So the post is just context. Look up the instrument, get a live quote, run the same checks as any other order, and send it down the normal path with a note on which post it came from.
Copying is that same flow, repeated every time the leader trades, and the FCA treats it as portfolio management unless the user confirms each trade. The engine has to run off the real trade events, never the feed, which can be delayed, held in moderation, or down. Each order goes out with an idempotency key, because a timed-out request the broker already accepted will open a second position if you just retry it. The first two rows are a realistic first release.
In Stream, the order never touches us. The ticket keeps the activity ID it came from, so a profile can show how many people duplicated the trader, and "someone you follow just opened a position" is a notification feed entry tied to that activity.
4. Chat and Comments Are Where People Explain Their Trades
A posted trade shows what someone bought, at what price, and when they sold. The comments are where the trader explains why, and where everyone else tells them they're wrong.
Real-world example:
TradingView's Minds are short posts attached to a symbol, and its House Rules apply to every one of them. Its own guidance asks for a line of reasoning with every setup and calls a bare "BUY: 90 | TP: 100 | SL: 85" low-effort.
(Source: TradingView)
Comments and chat are different jobs:
- A comment belongs to a trade, and it should still make sense a year later. Tie it to the activity's ID and record which version it was written against, so "nice entry" from when the position was open doesn't read as sarcasm after it closed at a loss.
- A chat channel belongs to a group of people, whether that's a private investing group, a one-to-one conversation, or a support session where the agent can see the account. Who's in it, the history, threads, who's read what, and what was delivered all have to match on a phone and a laptop, even after one of them has been offline for an hour.
Notifications need three separate settings: one for replies and mentions, one for what the traders you follow are doing, and one for account alerts. Someone who mutes a noisy community must not end up muting a margin call.
In Stream, comments, reactions, and the notification feed come with Feeds, so a reply on a trade lands in the same notification feed as the trade alerts. Channels are Chat, which handles threads, read receipts, offline sync, push, and exporting a channel's history for the archive. You decide who can join and what account information a message can include, and that check runs on your server, because hiding a channel in the app doesn't stop a client from asking for its messages by ID.
5. Moderation Has to Catch Market Abuse as Well as Bad Language
Moderation in a trading app is extremely tricky. Yes, a profanity filter will catch the bad language. But that isn't really what this is about. You want that gone, but what gets a trading community into trouble is a group of accounts pushing a thin stock, or someone saying "guaranteed returns" in replies, or someone pretending to be a well-known trader.
Real-world example:
Robinhood's user agreement bans anything that could look like market manipulation. It explicitly names:
- Pump and dump: talk up a stock you already hold to push the price up, then sell into the buying.
- Front running: trade ahead of an order you know is coming, so you profit from the move it causes.
- Marking the close: trade in the last minutes of the session to push the closing price where you want it.
- Painting the tape: trade a stock back and forth, often between accounts you control, so it looks busier than it is.
- Coordinated trading: a group agreeing to buy or sell the same thing at the same time to move the price.
- Insider trading: trading on material information the public doesn't have yet.
Along with promotions, professional investment advice, and posting personal information, wallet addresses are included. If in doubt, follow Bloomberg columnist Matt Levine's advice: everything is securities fraud.
Some violations you can see in one message, and those should be checked when a post is submitted. Each check lets it through, holds it for a person to look at, or rejects it:
- Links, against a list of known scam domains.
- Personal information, including anything that looks like a wallet address.
- Spam and repeat content.
- Text and image classifiers for whatever your policy bans.
Others you only see across accounts and over time. Say five accounts post the same ticker with similar wording within ten minutes, and two of them bought the stock an hour earlier. Only your trading data shows that second part. You need moderation algorithms in place to identify this coordinated fraud.
Taking a post down is not deleting it. FINRA's social media guidance says business-related posts on your own platform are records, and the SEC's recordkeeping rules only let you skip write-once storage if you can rebuild the original after any edit or deletion.
In Stream, Moderation does the checks on the way in, across text, images, and video, with the same rules on Chat and Feeds and a review queue for the held items. The cross-account cases and the archive stay on your side.
6. Live Video Brings Analysts and Advisors Into the Community
Text gets you a long way. At some point, though, people want to watch an analyst walk through a chart live, or get on a call with their own advisor.
Real-world example:
That's what Moomoo does with Moo Live. It posts upcoming earnings calls so you can book a seat, runs live Q&As with Nasdaq during earnings season, and posts replay clips afterward.
The thing that decides how you set it up is how many people get to talk:
- If people are talking to each other, you use WebRTC. The delay is under a second, people can take turns, and someone can share a chart from their screen.
- If one person is talking and thousands are watching, you use HLS, which is cheap to scale but runs several seconds behind, or WebRTC livestreaming, which keeps the delay low even with a big audience.
That delay is why live Q&A needs a timestamp. Send the viewer's playback position with each question, so the host knows which moment they're asking about.
Anything an advisor says on a call has to be kept the same way chat is, so before the first session, decide who's allowed to host, when recording starts, and what happens if the host's connection drops.
In Stream, an advisor call is a Video call with two people on it. A briefing is a livestream. The analyst publishes over WebRTC or pushes in from OBS over RTMP, viewers watch over WebRTC or HLS, and the chat sits next to it on Chat. You switch recording and transcription on per call, and the livestreaming guide walks through the latency tradeoff.
What to Build Yourself and What to Buy
The trading side should be a build: the performance numbers, the sharing rules, permissions, execution, the copy engine, and every compliance call. None of it can depend on a post being visible or a message getting through.
The social side is what is already available, and you can wire into your numbers:
| Capability | We run | You keep |
|---|---|---|
| Activity feeds | Follow graph, fan-out, feed groups, comments, reactions, ranking, real-time delivery | Turning executions into activities, the sharing rules, the instrument catalog, and what counts as relevant in the ranked feed |
| Messaging | Channels, threads, read state, offline sync, push, export | Who can join, what account information a message can include, supervision |
| Moderation | Text, image, and video checks, review queues, user reports | The market-abuse policy, surveillance, what gets kept and for how long |
| Live video | Calls, WebRTC and HLS livestreaming, RTMP ingest, recording, transcription | Who can host, Q&A timing, what happens to the recordings |
The order you build it in depends on what your app is for. If it's a trading app with a community on top, which is the usual case, go in this order:
- Profiles and the feed together. A trade post with no verified profile behind it isn't reliable.
- Comments. We strongly suggest turning on moderation the same day comments are enabled.
- Copy trading and live video, each as its own project with its own review.
If the app is built around something else, organize around that instead. An advisor platform is video-first, so calls come first, chat sits next to them, and the feed comes later, if at all. A copy-trading app is the copy engine first, and the feed is really there to help people find someone to copy.
Whichever way round, Feeds, Chat, Moderation, and Video cover the social side of all of it, and if you want to work out where the line sits for your platform, talk to us.