Short answer
Apps usually disagree for one of four reasons: one uses the Western tropical zodiac, they use different ayanamsas (the sidereal offset, about 24°14′ for Lahiri in November 2026), one shows your Sun sign rather than your Moon sign, or the birth time or timezone was entered differently. ChiChakra uses the Lahiri ayanamsa throughout.
How ChiChakra reads this
The Moon moves about 13° a day, so a one-degree difference in ayanamsa equals nearly two hours of the Moon's motion. That only changes your Rashi if the Moon was near a sign boundary when you were born, which is exactly when apps disagree.
How to settle it
1. Check the zodiac. If an app says 'tropical' or gives your newspaper star sign, it isn't comparable.
2. Check the ayanamsa. Lahiri, Raman and Krishnamurti (KP) are common choices and differ by small amounts.
3. Check what's being shown. Moon sign, Sun sign and Lagna are three different answers.
4. Check the inputs: the same birth time, place and timezone, including daylight saving.
If everything matches and the apps still disagree, you were probably born near a boundary. Pick the ayanamsa your astrologer or family tradition follows and use it consistently.
Good to know
Rahu and Ketu can differ between apps too, because some use the mean node and others the true node. ChiChakra uses the mean node.