SoStack vs Rndvu

SoStack is a communication and coordination platform built for real-world groups. Create private group chats, plan together with shared calendars, and follow verified public groups to stay up to date on what’s happening near you. What you can do with SoStack Private group messaging: Create 1:1 and group chats for friends, teams, families, and communities. Shared calendars + events: Create events in group calendars, add events to your own calendar view, and keep plans in one place. RSVP and planning: Mark events as interested/going and coordinate details with your group. Discover and follow public groups (SoStack Plus): Find local businesses, organizations, and communities, follow them, and see upcoming events and updates. Invite by phone: Invite people to private groups via SMS links, and optionally match contacts to existing SoStack users (with permission). Location-based discovery (optional): Use a city or current location to filter nearby results. Built with safety and control Account deletion in-app: Delete your account from Settings. Privacy-first by design: Messages are protected by access controls, and you control permissions like contacts and location in your device settings.

Rndvu is group messaging built around real plans. Most group chats are where plans go to die. Rndvu keeps the conversation and the plan in the same place — so the hike, dinner, game night, or trip actually happens, with the people who actually show up. GROUPS A private space for every crew — your hiking group, weekend runners, brunch club, ski friends, board game night. Real-time chat with photos, videos, voice messages, GIFs, polls, reactions and replies. Pin the message everyone keeps scrolling back to find. EVENTS Propose a plan, set a date and time, and see who's actually in. One-tap RSVP. Drop a location on a map, set a difficulty, attach a route or a parking PDF, and build a shared packing list anyone can tick off. A THREAD FOR EVERY PLAN Every event gets its own chat, so tonight's logistics don't get buried under last week's. Tap into the event, see the plan, talk it out. KNOW BEFORE YOU GO The forecast for the hour your event actually starts. Times shown in the venue's timezone, not yours. Reminders on your schedule, not ours. SHARED CALENDARS Sync your calendar and opt in with your crew. Find an open day shows the days everyone's actually free — no back-and-forth, no "are you around Saturday?" With Rndvu+, Find a free time narrows it to the hours that work for everyone. CATCH ME UP (RNDVU+) Been away from a busy thread? Tap Catch Me Up for a quick summary of the messages and events you missed while you were away. Powered by Gemini. PRIVATE BY DEFAULT Invite-only groups. Mute a thread, or just one person in it. Block and report built in. Delete your account and your data whenever you want. FREE VS. RNDVU+ Groups, chat, events, RSVPs, event threads and Find an open day are free for everyone. You never need Rndvu+ to join a group, RSVP, or show up. Rndvu+ is an optional subscription for whoever ends up planning for several crews: the live event map, AI catch-up summaries, Find a free time, higher-quality photos and video, themes and accent colors, route maps, hour-by-hour event weather and more. Free to try for a week; renews monthly or yearly until cancelled. Whether it's a Tuesday pickup game or a four-day backpacking trip, Rndvu keeps your people in the loop and the plan on the calendar.an on the calendar.