10bii Financial Calculator

Review by eFreeware

If you have ever needed a loan payment, an interest rate or a net present value worked out properly, the 10bii Financial Calculator is built for that job. It is a paid Android app from In A Day Development, priced at $5.99, and it carries a 4.4 average from 806 ratings across more than 50,000 installs. The pitch is a familiar one: the layout of Hewlett Packard's 10bII, softened for people who never learned the keystroke gymnastics that calculator demands.

The people most likely to want it are finance students working through time value of money problems, analysts sizing up a deal, and small-business owners comparing loan offers. It is also the kind of tool an instructor can put in front of a class to show how compounding behaves over a term. What you get in return is a calculator that does the arithmetic and then shows you why the answer came out that way, rather than leaving a number sitting on the screen with no context.

Built on the HP layout, with the keystrokes relaxed

The app follows the 10bII's arrangement of financial keys, so anyone with experience on that machine will recognize the terrain. The difference the developer emphasizes is that you can type whole equations and evaluate them with a single touch, which makes reviewing your own work far easier than stepping back through a register. The five core variables — N, I/YR, PV, PMT and FV — sit directly above their keys, so you can see the state of a calculation without hunting for it.

There is an Easy Mode that the developer describes as a way for anyone to reach the financial answer they need, which suggests a gentler path for people who do not want to think in terms of registers at all. A Help section holds video tutorials, and recent calculations are saved so you can reload an earlier problem instead of rebuilding it. Those two touches matter more than they sound: a financial calculator is only useful if you can get back to the work you did last week.

Time value of money, drawn out as a diagram

The core of the app is time value of money work: term length, present value, nominal interest, loan payments and future value. The Graph TVM key produces a cash flow diagram for a simple TVM setup, which turns an abstract set of inputs into something you can look at and check. When a sign is wrong or a payment is on the wrong side of the timeline, a picture is often faster to read than a table of numbers.

Nominal and effective interest rates switch with a single button, which is the sort of conversion that trips people up when they do it by hand. The developer lists more than 105 functions in total, covering financial analysis, business, statistics and general mathematics, so the app is not confined to loan math. It is billed as precise and intuitive, and the combination of an equation line and a visible variable row is what that claim rests on.

Uneven cash flows in a worksheet, not a register

Irregular cash flows are where financial calculators usually become unpleasant, and this app addresses that with a dedicated worksheet. You add, edit, delete and reorder entries in a spreadsheet-like grid, then let the app compute net present value and internal rate of return. Anyone who has modeled a project with a lumpy stream of costs and returns will recognize how much easier that is than keying values into numbered registers.

The app draws cash flow diagrams for complex uneven scenarios as well as simple ones, so the same visual check applies to a multi-year project. For a business owner weighing equipment purchases or a student working through an IRR problem, that combination of a worksheet and a diagram covers the two places mistakes usually hide. This app is the newer release of the earlier 10b, the developer says.

Amortization schedules you can hand to someone else

Amortization is handled as a first-class feature rather than an afterthought. Schedules can be printed or saved as PDF, and the most recent update added CSV export alongside the PDF option, which means the numbers can move into a spreadsheet for further work. If you need to show a client how a loan pays down over its term, having that output ready to send is a real convenience.

The statistics side covers standard deviation, mean and linear regression forecasting, which is enough for the descriptive and simple predictive work that comes up in business coursework. Recent changes also include support for Android 15 edge-to-edge displays and updates to the calculator and region settings screens, along with fixes to Easy Mode's past USA inflation handling and the Help menu. The app has been on Google Play since November 2010, and the April 2026 update suggests it is still being attended to.

What the $5.99 buys, and what sits behind the upgrade

The app costs $5.99 up front and contains no advertising. It does offer in-app purchases, and the developer identifies one of them directly: an upgrade that adds 10bii+ features covering bonds, breakeven, depreciation, trigonometry and probability. Those are the functions that take the app beyond the standard 10bII set, and they are the reason someone doing bond math or depreciation schedules would consider paying again.

The developer backs the purchase with a money-back guarantee and says support emails are generally answered within the hour. That is a promise rather than a feature, and it is worth treating as such, but it does tell you the developer expects problems to be resolvable. For a paid app with no ads, the value question is simply whether the functions you need are in the base price or behind the upgrade.

Alternatives worth weighing against it

The obvious comparison is a physical financial calculator, and the app's own framing invites it: it is modeled on a well-known Hewlett Packard model, so anyone who already owns that hardware is being asked to replace or duplicate it. The advantage of the app is that it lives on a phone you already carry, draws diagrams, and can export amortization schedules as PDF or CSV.

A spreadsheet on a laptop is the other realistic alternative, and it is stronger for large models and collaborative work. What the app offers instead is a purpose-built interface for TVM and uneven cash flow problems, with the variables visible above their keys and a diagram drawn for you. General-purpose finance apps are a third option, but they tend to be built around budgeting and tracking rather than calculation, which is a different job entirely.

A calculator for people who need to show their working

For a finance student, an analyst or a small-business owner who regularly works through loan payments, rates and project cash flows, this app looks like a well-considered tool. The price is a one-time $5.99 with no ads, and the upgrade adds the more specialized 10bii+ functions when you need them. The 4.4 average from 806 ratings is consistent with an app that does a narrow job and does it without much complaint.

The caveats are straightforward. It is a paid app, not a free one, and some of the more specialized functions sit behind an in-app purchase. It is also built around financial calculation rather than everyday money management. If your work involves time value of money, uneven cash flows or amortization schedules, the combination of visible variables, equation entry and drawn diagrams is a sensible reason to install it.

What's new in version 4.15

v4.12: Now export Amortizations as CSV in addition to PDF! Updated to support Android 15 edge-to-edge displays. v4.13: Updated Calculator Settings and Region Settings screens. v4.14: Fixed issue with Easy Mode: Past USA Inflation. v4.15: Fixed issues with Help menu.