What is the best alternative to Rumble Boxing - Group Fitness on iPhone?

Camp Gladiator, S tier, #1 in social workouts.

Is there a free alternative to Rumble Boxing - Group Fitness?

Yes: Camp Gladiator (S tier, #1) is free to download, with in-app purchases.

Yes. 1 app ranks above it in social workouts: Camp Gladiator (#1).

Rumble Boxing - Group Fitness is B tier, #2 of 6 in social workouts. Here is everything that competes with it on iPhone, in tier order.

1
Camp GladiatorShigher tier
Free + IAP · ★ 4.9 · 11,889 ratings · score 83
Group fitness app with live workout classes led by certified Personal Trainers, with new workouts starting every 5.
3
SugarWODB
Free · ★ 4.9 · 90,791 ratings · score 72
Workout tracking app for CrossFit-style athletes and affiliate gyms, with WOD posting, PR tracking, and community.
4
Zwift CompanionB
Free · ★ 4.7 · 27,352 ratings · score 71
Companion app for the Zwift indoor cycling and running platform, used to plan rides, control Zwift during workouts, and
5
Sweatpals: Fitness Near YouC
Free · ★ 4.9 · 5,561 ratings · score 69
Find and host fitness and wellness classes, events and retreats near you, with chat and ticketing for hosts and pals.
6
Echelon FitC
Free + IAP · ★ 4.4 · 8,352 ratings · score 65
Free fitness app with live, on-demand and scenic classes for cycling, rowing, running, strength training and yoga.

What is the best alternative to Rumble Boxing - Group Fitness on iPhone?: Camp Gladiator, S tier, #1 in social workouts.
Is there a free alternative to Rumble Boxing - Group Fitness?: Yes: Camp Gladiator (S tier, #1) is free to download, with in-app purchases.
Does anything rank above Rumble Boxing - Group Fitness?: Yes. 1 app ranks above it in social workouts: Camp Gladiator (#1).