Retire with the S&P 500 gives retired and people near retirement, a useful tool to look into the future and measure the various probabilities of the size of their ultimate estate. Retire with the S&P 500 illustrates a suggestion from Warren Buffett in his 2013 letter to stockholders. Mr. Buffett recommends the purchase of an S&P 500 index fund for the average individual investor, who has not made the study of business prospects a priority in their lives. This app enables users to vary their asset allocation to cash (short term treasury notes, CDs, money market fund deposits and fixed income investments) and an S&P 500 index fund. Retire with the S&P 500 presents the range of probabilities for the size of the ultimate estate based on four factors. 1. Value of their starting portfolio 2. Percentage held in bonds and cash equivalents 3. Yearly personal expense requirements 4. Years of life remaining Vary any factor and gain perspective on creating personal risk profiles and asset allocation models. From what I read, Retire with the S&P 500 simulates a retirement using S&P 500 Index data beginning in 1910 to present, using the actual historical S&P growth rates and inflation rates to generate possible outcomes into the future and their associated probabilities. Once the four variables are entered, the results are shown in simple, easy to read graphical and numerical form. There are other "financial calculators" offered by insurance companies, mutual funds and brokerage firms, however, who wants to risk conveying all their personal data to them? Using this app on my iPad only I can see the inputs and the results. This is a great app!