Roby: Rent vs. Buy Calculator

Name: Roby: Rent vs. Buy Calculator
Rating: 5 (4 reviews)
Author: Joshua Hart

Home Buying & Mortgage Planner

Free · In‑App Purchases · Designed for iPad. Not verified for macOS.

4 Ratings
Age Rating

18+
Years
Category

Finance
Developer

Joshua Hart
Language

EN
English
Size

5.2
MB

Your family says buying is always better. Your gut says the math doesn't add up. Roby shows you who's right. Roby runs detailed calculations so you can see where you stand. A mathematical illustration tool, not financial advice. Enter your zip code, your household income, and a few details about the home you're considering, and Roby pulls in local housing costs, tax rates, and insurance data for your state and county. Adjust 25+ financial inputs — from loan type to filing status to marginal tax bracket — and watch the estimate update in real time. SEE THE FULL PICTURE • Month-by-month break-even timeline over up to 30 years • Interactive charts showing estimated net position, monthly costs, and the crossover point • Side-by-side rent vs. buy cost comparison • Accounts for mortgage interest deductions, PMI, SALT caps, and more YOUR SITUATION, NOT A GENERIC ESTIMATE • County-level median home prices and local tax rates • Conventional, FHA, and VA loan structures with accurate mechanics • Household income, partner income, filing status, and bracket-aware tax modeling • Inflation-adjusted estimates in today's dollars THE TAX BREAK REALITY CHECK Roby doesn't assume you'll get a "mortgage interest deduction" tax break. It compares your estimated itemized deductions against the standard deduction at your bracket and filing status, and tells you whether the tax break would actually materialize at your income — or whether the math should ignore it. UNDERSTAND THE WHY, NOT JUST THE WHAT Unlock 17 detailed illustration sections that go beyond the numbers: • Required household income to stay under the classic 28% housing rule • A stricter 25%-of-take-home second opinion • Back-end DTI headroom, retirement-savings room, and job-loss reserve target • Wage-growth glide path — when a tight payment gets comfortable as income rises • Equity vs. invested-instead wealth comparison • Joint-filer income shock test: what if only one of you was earning? • Year-by-year checkpoints and landmark moments • What-if scenarios and the levers you can pull BUILT FOR TRUST • One-time purchase. No subscription. No ads. • All calculations run on your device — your data never leaves your phone • Transparent data sources: Census Bureau, FRED, Tax Foundation, IRS • All estimates are hypothetical, based on your assumptions. Not a substitute for professional advice. EXPORT & SHARE Generate a PDF report with your full analysis to share with a partner, family, or financial advisor. Homeownership is a major financial commitment. See what the numbers say for your situation.

Ratings & Reviews

5.0

out of 5

4 Ratings

First Time Budgeting
Apr 9
Kate_hart
As someone who is very young and has struggled with learning about things like the housing economy, this app definitely helps. I immediately noticed how you can enter your location and Roby will tell you the average house and renting costs in your area. It helps give you insight in what to expect.While a lot of the language feels foreign to me, Roby provides the “Explain It” feature, which helps you decide if you’re making a dumb decision or not. Why wait for weeks to get a reply about if you’re making a good idea or not, if you can just get it in seconds?If you’re stressed out and trying to navigate your budget with housing or renting, this app is definitely it. The developer has people’s best interest in mind , which makes me more comfortable using this app, knowing it is not just a money grab. I think one improvement I’d like to see would maybe be a little tutorial/introductory page when you first get the app. Helping to navigate it and understanding what things are and how to exactly work it would be a huge plus, especially for people (like me) who get immediately stressed out with the lack of guidance and direction. Although I understand that that would probably be part of the Explain It feature. It would be cool if it could add listings in your area, and suggest homes or rentals that fit your budget! Notifications that pop up right when there is a listing so you don’t miss out. Overall, great app with the best intentions! I highly recommend this app if you are looking to purchase a home or rent something! :)
First Time Budgeting
Apr 9
Kate_hart

As someone who is very young and has struggled with learning about things like the housing economy, this app definitely helps. I immediately noticed how you can enter your location and Roby will tell you the average house and renting costs in your area. It helps give you insight in what to expect.While a lot of the language feels foreign to me, Roby provides the “Explain It” feature, which helps you decide if you’re making a dumb decision or not. Why wait for weeks to get a reply about if you’re making a good idea or not, if you can just get it in seconds?If you’re stressed out and trying to navigate your budget with housing or renting, this app is definitely it. The developer has people’s best interest in mind , which makes me more comfortable using this app, knowing it is not just a money grab. I think one improvement I’d like to see would maybe be a little tutorial/introductory page when you first get the app. Helping to navigate it and understanding what things are and how to exactly work it would be a huge plus, especially for people (like me) who get immediately stressed out with the lack of guidance and direction. Although I understand that that would probably be part of the Explain It feature. It would be cool if it could add listings in your area, and suggest homes or rentals that fit your budget! Notifications that pop up right when there is a listing so you don’t miss out. Overall, great app with the best intentions! I highly recommend this app if you are looking to purchase a home or rent something! :)
This app blows the other apps out of the water
Apr 16
Darku2.0
This app is crazy for all the features! I bought the premium explanation, and I don’t regret it one bit. The reasons this app is so easy to use, is that you just enter your info (I appreciate the privacy guards) and the app does all the rest. I easily can see how my current loan spans across 30 years and I specifically loved that I could share this analysis with my realtor!
This app blows the other apps out of the water
Apr 16
Darku2.0

This app is crazy for all the features! I bought the premium explanation, and I don’t regret it one bit. The reasons this app is so easy to use, is that you just enter your info (I appreciate the privacy guards) and the app does all the rest. I easily can see how my current loan spans across 30 years and I specifically loved that I could share this analysis with my realtor!
Finally one I can understand
Apr 9
Bunnies88
Thanks for putting this in plain English! I had another one that was all in finance terms and if I knew what all of that meant, I wouldn’t need help deciding! This app is great!
Finally one I can understand
Apr 9
Bunnies88

Thanks for putting this in plain English! I had another one that was all in finance terms and if I knew what all of that meant, I wouldn’t need help deciding! This app is great!

Roby now takes your household income and filing status, and uses them to answer the questions a rent-vs-buy calculator actually should. • The Tax Break Reality Check: does the mortgage interest deduction actually lower your tax bill, or does the standard deduction win? • Required income, retirement room, back-end DTI headroom, and a job-loss reserve target tailored to your numbers. • The Glide Path: when a tight payment gets comfortable as income rises. • A second opinion against the stricter 25%-of-take-home rule. Plus 17 premium sections (up from 15).

Version 1.0.1 Apr 12

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Supported Features
- VoiceOver
- Voice Control
- Larger Text
- Dark Interface
- Differentiate Without Color Alone
- Sufficient Contrast
- Reduced Motion

Information

Seller: Joshua Hart
Size: 5.2 MB
Category: Finance
Compatibility: Requires iOS 18.0 or later.

iPhone
Requires iOS 18.0 or later.

iPad
Requires iPadOS 18.0 or later.

Mac
Requires macOS 15.0 or later and a Mac with Apple M1 chip or later.

Apple Vision
Requires visionOS 2.0 or later.
Languages: English
Age Rating: 18+

18+

Learn More
In-App Purchases: Yes

Premium Analysis $2.99

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