Name: Community Forum App
Availability: InStock

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Community Forum App

Topic boards where people post and talk

A complete Reddit-style community forum starter. Join topic boards, post a title and body with an optional image, and reply in threaded comments at any depth. Up/down vote rails drive author karma, with Hot / New / Top sort tabs across feeds. Save posts and get a notification inbox for replies and upvotes. Backed by a real Supabase schema with Auth, Row Level Security, karma and counter triggers, Storage, and Realtime.

Topic boards you join, with a cross-board Home feed
Posts with title, body, optional image, and up/down vote rail
Threaded comments with inline reply composer at any depth
Hot / New / Top sort tabs, save posts, and a reply/upvote inbox
Profile with karma and Posts / Saved / Activity sub-tabs
Full Supabase schema: Auth, RLS, karma + counter triggers, Storage

Use this template

What you can do

This is a community app where people gather around topics they care about, kind of like Reddit. You join boards on subjects that interest you, share a post with a title, a few words, and an optional photo, and reply back and forth in tidy comment threads at any depth. You can give a thumbs up or thumbs down to posts and replies (which builds the author's karma), save the ones you want to return to, and get a notification when someone replies to you or upvotes a post you wrote. It runs on your own Supabase project, so it opens on a Connect screen and a sign-in step first; there is also a one-tap sample-data preview if you just want to look around before wiring up a backend.

Made forAnyone starting an online community around a hobby, brand, town, or shared interest.

Join topic boards and read a single cross-board Home feed
Sort any feed by Hot, New, or Top
Write a post with a title, body, and an optional image
Reply in threaded comment chains with an inline composer at any depth
Up- or down-vote posts and replies, which builds author karma
Save posts to come back to later
Get a notification inbox when someone replies to or upvotes you

Under the hood

For developers: exactly what is included when you start from this template, taken straight from the template's own code.

Stack

Expo SDK 54React Native 0.81React 19TypeScript 5.9Supabase (Postgres, Auth, Realtime, Storage) via supabase-js 2.45expo-image-picker 17 for post imagesreact-native-svg 15.12react-native-safe-area-context 5.6react-native-web 0.21

Screens

Connect
Shown until your Supabase backend is wired up, with a one-tap sample-data preview to explore first.
Sign in
Real Supabase email and password sign-in and sign-up before you reach the forum.
Home
Cross-board feed of the boards you have joined with Hot, New, and Top sort tabs and pull to refresh.
Explore
Search the full board catalogue and join or leave any board with one tap.
Board
A board's header, member count, Join button, sticky sort tabs, and its post list.
Post
The expanded post with an up/down vote rail and save, followed by threaded comments and a reply composer.
Compose
Pick a board, write a title and body with a live character counter, and attach an optional image.
Profile
Your karma and post/comment counts with Posts, Saved, and Activity (reply and upvote inbox) sub-tabs.
Settings
Edit your display name, username, and bio, and sign out.

Data model

profiles
One row per user with username, display_name, bio, avatar_url, and denormalized karma, post_count, and comment_count.
boards
Topic containers with slug, name, description, cover_url, and cached member_count and post_count.
board_members
Join pivot of board_id and user_id that drives member_count and the joined flag.
posts
Threads inside a board with title, body, image_url, and cached upvote_count and comment_count.
post_votes
Per-user post vote with a value of -1 or 1 that drives a post's upvote_count and the author's karma.
comments
Replies on a post, threaded via a self-referencing parent_id, with a cached upvote_count.
comment_votes
Per-user comment vote with a value of -1 or 1 feeding comment upvote_count and author karma.
saved_posts
Private pivot of post_id and user_id that drives the viewer's saved flag.
notifications
Private recipient inbox of kind 'reply' or 'upvote', with actor_id, optional post_id/comment_id, and a read flag.

Backend

RLS on every table: profiles, boards, board_members, posts, post_votes, comments, and comment_votes are world-readable while writes are scoped to the owner via auth.uid(); saved_posts and notifications are private to the user, and notifications has no insert policy so only triggers create them.
Counter triggers keep denormalized fields in sync so feeds never aggregate at read time: on_post_change maintains post_count, on_member_change maintains member_count, on_comment_change maintains comment_count, on_post_vote maintains a post's upvote_count, and on_comment_vote maintains a comment's upvote_count.
Karma is maintained by on_post_vote and on_comment_vote (only when the voter is not the author), and reverse_post_karma and reverse_comment_karma run before a post or comment is deleted to undo the karma it earned before its votes cascade away.
Notification triggers auto-insert a 'reply' row to the parent comment or post author (on_comment_change) and an 'upvote' row to the post author on a fresh +1 (on_post_vote), skipping self-actions.
A handle_new_user trigger on auth.users (SECURITY DEFINER) auto-provisions a profile on signup, deriving a slugified username and retrying with a numeric suffix to guarantee uniqueness under concurrent signups.
Realtime: the supabase_realtime publication includes boards, board_members, posts, post_votes, comments, comment_votes, saved_posts, and notifications for live feed, vote, comment, and inbox updates.
Storage: a public 'post-images' bucket (5 MB limit, jpeg/png/webp only) is created with owner-folder RLS so users can only write to a folder named after their own auth.uid(). No Edge Functions; all counter, karma, and notification logic lives in database triggers.

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Built with Appsanic

Community Forum App

Topic boards where people post and talk

Topic boards you join, with a cross-board Home feed
Posts with title, body, optional image, and up/down vote rail
Threaded comments with inline reply composer at any depth
Hot / New / Top sort tabs, save posts, and a reply/upvote inbox
Profile with karma and Posts / Saved / Activity sub-tabs
Full Supabase schema: Auth, RLS, karma + counter triggers, Storage

Use this template

What you can do

Made forAnyone starting an online community around a hobby, brand, town, or shared interest.

Join topic boards and read a single cross-board Home feed
Sort any feed by Hot, New, or Top
Write a post with a title, body, and an optional image
Reply in threaded comment chains with an inline composer at any depth
Up- or down-vote posts and replies, which builds author karma
Save posts to come back to later
Get a notification inbox when someone replies to or upvotes you

Under the hood

For developers: exactly what is included when you start from this template, taken straight from the template's own code.

Stack

Screens

Connect
Shown until your Supabase backend is wired up, with a one-tap sample-data preview to explore first.
Sign in
Real Supabase email and password sign-in and sign-up before you reach the forum.
Home
Cross-board feed of the boards you have joined with Hot, New, and Top sort tabs and pull to refresh.
Explore
Search the full board catalogue and join or leave any board with one tap.
Board
A board's header, member count, Join button, sticky sort tabs, and its post list.
Post
The expanded post with an up/down vote rail and save, followed by threaded comments and a reply composer.
Compose
Pick a board, write a title and body with a live character counter, and attach an optional image.
Profile
Your karma and post/comment counts with Posts, Saved, and Activity (reply and upvote inbox) sub-tabs.
Settings
Edit your display name, username, and bio, and sign out.

Data model

profiles
One row per user with username, display_name, bio, avatar_url, and denormalized karma, post_count, and comment_count.
boards
Topic containers with slug, name, description, cover_url, and cached member_count and post_count.
board_members
Join pivot of board_id and user_id that drives member_count and the joined flag.
posts
Threads inside a board with title, body, image_url, and cached upvote_count and comment_count.
post_votes
Per-user post vote with a value of -1 or 1 that drives a post's upvote_count and the author's karma.
comments
Replies on a post, threaded via a self-referencing parent_id, with a cached upvote_count.
comment_votes
Per-user comment vote with a value of -1 or 1 feeding comment upvote_count and author karma.
saved_posts
Private pivot of post_id and user_id that drives the viewer's saved flag.
notifications
Private recipient inbox of kind 'reply' or 'upvote', with actor_id, optional post_id/comment_id, and a read flag.

Backend

RLS on every table: profiles, boards, board_members, posts, post_votes, comments, and comment_votes are world-readable while writes are scoped to the owner via auth.uid(); saved_posts and notifications are private to the user, and notifications has no insert policy so only triggers create them.
Counter triggers keep denormalized fields in sync so feeds never aggregate at read time: on_post_change maintains post_count, on_member_change maintains member_count, on_comment_change maintains comment_count, on_post_vote maintains a post's upvote_count, and on_comment_vote maintains a comment's upvote_count.
Karma is maintained by on_post_vote and on_comment_vote (only when the voter is not the author), and reverse_post_karma and reverse_comment_karma run before a post or comment is deleted to undo the karma it earned before its votes cascade away.
Notification triggers auto-insert a 'reply' row to the parent comment or post author (on_comment_change) and an 'upvote' row to the post author on a fresh +1 (on_post_vote), skipping self-actions.
A handle_new_user trigger on auth.users (SECURITY DEFINER) auto-provisions a profile on signup, deriving a slugified username and retrying with a numeric suffix to guarantee uniqueness under concurrent signups.
Realtime: the supabase_realtime publication includes boards, board_members, posts, post_votes, comments, comment_votes, saved_posts, and notifications for live feed, vote, comment, and inbox updates.
Storage: a public 'post-images' bucket (5 MB limit, jpeg/png/webp only) is created with owner-folder RLS so users can only write to a folder named after their own auth.uid(). No Edge Functions; all counter, karma, and notification logic lives in database triggers.