Fixed Income Bonds Simplified2026.10 - App Store

Understand what changes a bond’s price-and why.

Bonds: Simplified is a hands-on fixed-income workbench for finance students and practitioners learning, checking or explaining bond math. Change the assumptions, compare scenarios and connect the numbers to price, cash flows and rate risk.

EXPLORE PRICE AND RISK
Calculate fixed-rate bond prices and yields. Examine duration, convexity and rate sensitivity, then compare scenarios side by side.

LEARN THE MECHANICS
Build your vocabulary with the Bond Fundamentals track and glossary. Use interactive demonstrations to explore fixed-income concepts.

GO DEEPER
Analyze callable bonds and mortgage-backed securities. Explore call assumptions, prepayment speeds, projected cash flows and sensitivity results.

CONNECT THE CURVE TO THE CALCULATION
Explore Treasury curves, historical comparisons and rate trends, with observation dates shown.

KEEP YOUR WORK
Save comparison pairs and export summaries for further analysis or discussion.

For students developing fixed-income intuition and practitioners who want a portable way to explore and explain scenarios.

Calculations are estimates based on your inputs and model assumptions. They are for education and analysis and should not be relied upon for investment transactions.

Version History A little housekeeping: small bug fixes and performance improvements.

Requires iOS 26.2 or later. 2026.10 1d ago This is our biggest update yet — a new Historical Yield Curve, home-screen widgets, a rebuilt Rates experience, and side-by-side comparison workflows for every instrument type.

HISTORICAL YIELD CURVE
Compare any two published Treasury curves side by side, then drag the timeline or press play to watch a year of history move. Every curve is labeled with its shape — Normal, Flat, Inverted, or Humped — and every date pair with how it moved, from Bull Steepener to Bear Flattener. Open "Why this label?" to see the exact thresholds behind the call and the literature they come from. Dates are chosen from a calendar limited to real publication days, and an exact-values table backs up every point on the chart.

HOME SCREEN & LOCK SCREEN WIDGETS
Track the Treasury yield curve and 30-/15-year mortgage rates at a glance. Small, medium, large, and Lock Screen sizes — each with a clear as-of date, so you always know how fresh the data is. Widgets now refresh automatically from our rate service, and tapping any widget jumps straight to the Rates tab.

A BIGGER, FASTER RATES TAB
Treasury yields now sit alongside SOFR, the Effective Fed Funds Rate, and Freddie Mac mortgage averages. Explore interactive trend charts with years of history, overlay today's yield curve against one year ago, and scan 12-month sparklines on every rate row. Every rate is labeled with its true observation date and clear, self-describing change indicators, so you always know exactly what you're comparing. Rate delivery moved to a faster, more reliable service with stronger offline caching.

COMPARE ANY TWO BONDS SIDE-BY-SIDE
Full comparison workflows for fixed rate, callable, and MBS bonds: delta tables, comparison charts for cash flows, price sensitivity, call probability, and prepayment behavior, plus portfolio lenses (Neutral, Income, Rate Defense, Extension Defense, Option Cost) and a methodology sheet showing the assumptions behind every number. Export summaries to CSV or PDF, save comparison pairs, and reopen them later fully recalculated.

SIRI, SHORTCUTS & SPOTLIGHT
Ask for a Treasury yield, open today's yield curve, or look up glossary terms from Siri, Shortcuts, or system search.

LEARN BOND FUNDAMENTALS
Bond Fundamentals is a new guided learning track — ten short lessons building the vocabulary for reading bond prices, cash flows, and risk, with your progress saved as you go. It sits on an expanded 104-term glossary, and Learn now opens on a hub that puts your track progress, recently viewed terms, and search on one screen. Start typing to filter every definition, or browse the full glossary by category, with bookmarks and interactive concept demonstrations throughout.

REDESIGNED FOR iPAD
Comparison workbench layouts, menu bar commands, and keyboard shortcuts across Fixed Rate, Callable, and MBS workflows.

SHARPER NUMBERS
Settlement-aware bond pricing, ISDA-exact ACT/ACT day counts, and a hardened MBS yield solver.

A WELCOME THAT ASKS NOTHING
No account, no setup, no forms. The first run opens on today's published Treasury curve, plays the last ten years of it in a few seconds, then hands you a live bond and one control: drag the yield and watch the price move. Tap through and you land in the calculator with that same yield already loaded, ready to change anything else. Skip it whenever you like, or replay it later from Settings.

Plus haptic feedback, a refreshed design language, Dynamic Type across the calculation screens — metric tables, buttons, and input fields now follow your Larger Text setting — and hundreds of quality and accessibility fixes. 2026.9 Sep 14 Compare MBS bonds side-by-side and analyze prepayments like never before

NEW: MBS BOND COMPARISON
Compare two mortgage-backed securities simultaneously with fully configurable parameters. A unified rate slider shows how both bonds respond to interest rate changes, with instant delta calculations for price, yield, WAL, and duration.

REDESIGNED PREPAYMENT ANALYSIS
A streamlined interface brings rate shocks, horizon analysis, and scenario comparisons together in one view. Quick navigation lets you jump between sections, and smarter PSA bounds ensure realistic modeling.

DELTA COMPARISON MODE
New toggle between absolute and percentage changes when comparing rate shock scenarios. See exactly how metrics shift across different rate environments.

ENHANCED ACCESSIBILITY
Comprehensive VoiceOver support throughout the app. Every chart, table, and interactive element now provides rich descriptions, making professional bond analytics accessible to everyone.

FASTER & MORE RELIABLE
Optimized calculations with better memory management. Rate data refreshes intelligently while keeping yield curves current. 2026.1 Jan 19 Significant redesign on iPad.
Addition of callable fixed-rate bonds.
Initial interactive education functionality.
Bug fixes all over the place. 2025.12 12/19/2025 New Component Architecture Update
• Button interactions - All buttons should feel more responsive with improved touch targets and visual feedback
• Card layouts - Information cards and expandable sections should display content more clearly and consistently
• Chart performance - MBS cash flow charts should load faster and interact more smoothly
• Form inputs - Number and rate fields should validate input better and format numbers consistently
• Navigation flow - Moving between calculation screens should feel smoother with better transitions
• Visual polish - Overall app should feel more cohesive with improved spacing, colors, and typography
• Settings & exports - Export functionality and settings screens should be more intuitive to use 2025.10 09/18/2025 WHAT'S NEW IN THIS VERSION
• Complete UI overhaul with modern Apple design language and enhanced visual hierarchy
• Rebuilt from the ground up with SwiftUI for smoother performance and native iOS experience
• New tabbed navigation architecture for intuitive access to calculations, education, and market data
• Interactive scenario builder with real-time parameter adjustments and instant visual feedback
• Comprehensive educational hub with searchable bond terminology and calculation explanations
• Enhanced chart visualizations with multi-dimensional data representation
• Streamlined calculation workflows that reduce steps while increasing analytical depth
• Improved accessibility with VoiceOver support and Dynamic Type scaling 2025.9 09/16/2025 Minor bug fixes and edits. If there is some calculation or functionality you'd like to see included please don't hesitate to ask!

*** STAY TUNED ***
Currently working on adding additional educational features and simple calculators to help more users understand the basics. 1.2 05/01/2022 - Adds basic Agency CMBS calculations
- Cleans up the retrieval process for yield curve information
- Bug fixes related to markers when selecting data on cash flow charts
- Bug fixed related to email export of cash flows 1.1 08/21/2019 1.0 08/24/2017