SolarWriter vs QuantFit

Traditional screens are fantastic everywhere but outside, especially on a sunny day. E-ink screens work well, but e-readers like the Kindle are difficult to type on and don't support external keyboards. SolarWriter gives you the best of both worlds. SolarWriter runs on your iOS device and acts as a hub between your keyboard and your e-reader. You type on the keyboard, and the text appears on both on the iOS device and on the e-reader's screen (via its web browser). Take advantage of your Kindle's (or other e-reader's) e-ink screen to put your thoughts on paper even outside, with no need to transcribe later. Write at parks, on beaches, in backyards... anywhere you wanted to but couldn't. Save files on your device, or share through email, SMS, and more. Detailed instructions for setup are included inside the app.

QuantFit is a research-grade econometrics workbench for iPhone and iPad. Run real regressions on real data, anywhere. ESTIMATORS • Cross-section and panel: OLS, Fixed Effects, Random Effects, 2SLS / instrumental variables • Time-series cointegration: ARDL bounds testing, NARDL with asymmetric long-run and short-run dynamics, FMOLS, DOLS, CCR • System estimators: VAR with Cholesky impulse-response and forecast-error variance decomposition, VECM with cointegrating rank • Panel dynamic: Pooled Mean Group, Mean Group, Dynamic Fixed Effects, CS-ARDL, Common Correlated Effects • Dynamic GMM: Arellano-Bond difference GMM, Blundell-Bond system GMM, with Windmeijer finite-sample standard errors LIVE DATA Pull data straight into your regressions from World Bank, IMF World Economic Outlook, IMF International Financial Statistics, Penn World Table, and FRED. Country pickers, automatic frequency detection, ragged-panel handling, and multi-frequency support (annual, quarterly, monthly, weekly, daily) are built in. Upload your own CSV or XLSX file too. PUBLICATION OUTPUT Every result renders in a clean coefficient table with significance stars, confidence intervals, and academic-style diagnostic blocks. One-tap exports to LaTeX, PNG, CSV, Excel, and clipboard. Save coefficient plots, actual-vs-fitted, residual diagnostics, and Q-Q plots as publication-ready PNGs. POST-ESTIMATION Residual diagnostics including Ljung-Box, White heteroscedasticity, Jarque-Bera, plus a full residual unit-root suite (ADF, KPSS, DF-GLS, Zivot-Andrews). Save residuals to your dataset and re-diagnose them in one tap. Auto-generated academic paper draft with abstract, methodology, and results narrative. R script export with method-specific packages. WHO IT IS FOR Empirical researchers, PhD students, policy analysts, and economists working with macro, finance, trade, development, or panel data. Anyone who wants to run a real regression on real data without opening a desktop stats package. SHOCK BUILDER Take any estimated regression and run policy or scenario shocks against it. Specify shock magnitudes for any subset of regressors, simulate the dependent variable's response over your chosen horizon, and read the result as a fan chart with confidence bands. Useful for policy counterfactuals, climate scenarios, exchange-rate pass-through, or any "what if X moved by Y" question your model can answer. QuantFit is fast, honest, and academic. No black boxes, no shortcuts, no ads. https://www.apple.com/legal/internet-services/itunes/dev/stdeula/