About OIOA
What is OIOA?
OIOA (One India One App) is a free app built around Indian families. It has a family tree that records tithis and remembrance dates, shared contacts that reach every family member’s phone book, events that ring for everyone, and each community’s own calendar and daily timings, offline. See why OIOA is different.
Which communities does OIOA cover?
OIOA covers the Hindu, Islamic, Jain, Parsi and Sikh/Punjabi communities, each with its own Home screen. We are open to adding any community that asks. Request a community.
Why is it called One India One App?
Because the idea is simple: one app where every community’s calendar sits side by side, with equal care. It is a humble attempt to reflect the brotherhood that is already part of everyday Indian life. Read our purpose.
Is any community given priority in the app?
No. Every community has its own Home screen with the same depth, and on this website communities are listed alphabetically. If anything feels unequal, please tell us.
Is OIOA affiliated with any religious organisation or government body?
No. OIOA is independent and is not affiliated with any religious, sectarian or governmental body. Calendar content follows traditional, astronomical and mathematical methods; please follow your own community’s authority. See the disclaimer.
Is OIOA free?
Yes. OIOA is free to download and use. There are no paid features at present. The app may show advertisements, and some extra card backgrounds can optionally be unlocked by watching a rewarded video; free designs always remain available. See the Terms of Use.
Download and devices
Is OIOA available on iPhone as well as Android?
OIOA is being made for both Android and iPhone (iOS). Store links are on the download page and appear as soon as each listing is public.
Do I need an account to use OIOA?
No. Calendars, timings, tools, cards and personal reminders work without an account. Shared features (Family, Family Tree, Groups and shared contacts) need an OIOA-ID, which you create with your name and a recovery email. See OIOA-ID and sync.
Can I use OIOA on more than one phone?
Yes. Calendar timings work on any phone. To bring your Families, Family Trees and Groups to a new phone, choose Claim / Recover with your OIOA-ID or recovery email, then tap SYNC. Personal events, calendar notes and prediction profiles are stored only on the phone where you made them.
Communities and calendars
How do I switch to a different community?
Open Settings in the app and choose a community. The Home screen changes immediately. You can switch back at any time.
Why do dates in OIOA sometimes differ from my local calendar?
Calendar dates and timings depend on location, on the method used (for example Amanta or Purnimanta months, or a particular prayer-time method) and on local custom. OIOA calculates for your location with the method you choose, but some communities fix dates by local announcement or moon sighting. Always follow your own community’s authority. Why dates differ.
Will you publish festival dates for the coming year?
Festival pages on this website explain what each festival marks and how OIOA helps you plan. We publish exact future dates only when they come from verified data, because many dates depend on location, method or announcement. See festivals.
My community or sect isn't listed. Can you add it?
Very likely. OIOA is open to adding any community that asks. Use the request form to tell us the community, what it needs and a source we can check. Every request is read by a person.
Which calendar systems does OIOA explain?
The Hindu panchang, Vikram Samvat, Shaka Samvat, the Jain calendar, the Hijri calendar, the Parsi calendars and the Nanakshahi calendar.
Hindu panchang and timings
What does the Hindu panchang in OIOA include?
Tithi, the 27 nakshatras, paksha, the lunar month and Adhik maas, plus Choghadiya, Hora, Rahu Kaal, Abhijit muhurat, sunrise and sunset, and Panchak while it is running. See the panchang feature.
What is the Today card?
The Today card on the Home screen shows the day at a glance. Its live sliders let you move through the day and see which timings apply at any moment.
Why does OIOA show Panchak only sometimes?
Panchak happens only while the Moon passes through the last five nakshatras, a few days each lunar month. OIOA shows it only while it is running so the Home screen stays uncluttered. About Panchak.
Is Rahu Kaal the same everywhere in India?
No. Rahu Kaal is a fixed eighth of the daylight, so it shifts with your local sunrise and sunset. OIOA works it out for your location. How Rahu Kaal is worked out.
Does OIOA use Amanta or Purnimanta months?
Month naming differs by region: Amanta months end on the new moon and Purnimanta months end on the full moon. Purnimanta and Amanta explained.
What is Adhik maas and does OIOA show it?
Adhik maas is an extra lunar month added roughly every 32 to 33 months to keep the lunar calendar in step with the seasons. OIOA’s panchang shows it when it occurs. Adhik maas explained.
Islamic prayer times and calendar
Which prayer-time calculation methods does OIOA support?
Karachi (University of Islamic Sciences), Muslim World League, ISNA, Egyptian, Umm al-Qura, Tehran and Jafari/Qum, with Standard or Hanafi Asr. Choose the method your mosque or community follows. Prayer times and Qibla.
Does OIOA show Jumma time?
The Friday prayer is held in the Dhuhr period, and its khutbah and jamaat times are set by each mosque. OIOA lets you set your mosque’s Jumu’ah time so it appears alongside the calculated prayer times.
How does OIOA find the Qibla direction?
It calculates the great-circle bearing from your location to the Kaaba in Makkah. Your phone’s compass then points the way, so calibrate it and keep away from metal. How Qibla is calculated.
Which Islamic calendar options are available?
The Islamic calendar with Shia, Bohra (Dawoodi and Misri) and Makkah (Umm al-Qura) options. The Hijri calendar.
Why might the Islamic date in OIOA differ from the local announcement?
Many communities begin months by sighting the new crescent, which can differ by a day from a calculated calendar. OIOA lets you pick the calendar option you follow; for occasions that depend on sighting, please follow your local announcement. Moon sighting and Umm al-Qura.
Jain calendar
What does the Jain section include?
Everything in the panchang, plus the 28 Jain nakshatras, Navkarshi times and sect-aware calendars. See the Jain community page.
Which Jain sects' calendars are supported?
Shwetamber, Digamber, Khartargachh, Sthanakwasi and others. If yours isn’t covered, please request it.
What is Navkarshi?
Navkarshi is a morning practice of not eating or drinking until 48 minutes after sunrise. OIOA shows the Navkarshi time for your location each day. Navkarshi explained.
Why are there 28 nakshatras in the Jain tradition?
The Jain list includes Abhijit, placed between Uttara Ashadha and Shravana, making 28. The 28 nakshatras.
Parsi calendar
Which Parsi calendars does OIOA support?
Shahenshahi, Kadmi and Fasli. Choose the one you follow and OIOA shows the Roj and Mah for it. Parsi calendar methods.
Does OIOA show the Gahambars?
Yes. The six Gahambars appear through the year according to the calendar you choose. The Gahambars.
Why does Navroz fall on different dates for different Parsis?
The Fasli calendar keeps Navroz on 21 March, while the Shahenshahi and Kadmi calendars have no leap day and so move through the seasons, with Kadmi a month ahead of Shahenshahi. Shahenshahi, Kadmi and Fasli.
Sikh / Punjabi calendar
Which Nanakshahi calendar does OIOA use?
You can choose the original 2003 Nanakshahi calendar or the SGPC method. The two versions explained.
Why do some gurpurab dates change every year?
In the SGPC method several gurpurabs follow lunar dates, so their Gregorian dates move from year to year. In the original 2003 calendar they are fixed solar dates. Nanakshahi calendar history.
Languages
Which languages is OIOA available in?
English plus Gujarati, Hindi, Marathi, Bengali, Tamil, Telugu, Kannada, Malayalam, Odia, Assamese, Punjabi, Arabic and Urdu. All languages.
How do I change the app's language?
Use the EN ⇄ local-language toggle. It switches the whole page between English and the language you’ve chosen.
Can you add my language?
More languages are welcome. Tell us which language and, if you can, whether you’d be willing to help check translations.
Offline use, privacy and data
Does OIOA work without the internet?
Yes. Calendar calculations run on your phone, so daily timings don’t depend on a network connection. Shared features save your changes on the phone first and need a connection only when you tap SYNC. Offline calendars.
Why does OIOA ask for my location?
Sunrise, sunset, muhurat windows, prayer times and Qibla all depend on where you are. You can allow location or pick a city from the built-in list instead. The Qibla screen asks each time and uses your location once, only for that action. See the privacy policy.
Why does OIOA ask for access to my contacts?
Only if you turn on phone contact export for a Family or Group. OIOA then writes that shared list into your phone’s Contacts app and keeps it updated. It never uploads your address book and never changes or deletes a contact it didn’t create. Shared contacts.
Are my birth details used for daily predictions stored on a server?
No. Prediction profiles (name, birth date, time and place) are stored on your phone only, and readings are calculated there. See the privacy policy.
How do I delete my data?
You can ask for your data to be erased at any time. The privacy policy explains how, and the grievance page lists who to contact.
Can children use OIOA?
Users under 18 need the verifiable consent of a parent or lawful guardian, as described in the privacy policy.
Everyday tools
Does OIOA show state holidays as well as national holidays?
Yes. OIOA shows national, state and bank holidays for every state and union territory, and its planner suggests long weekends from your own weekly offs and leave budget. Provisional entries are labelled. Holidays and long weekends.
How accurate is the GST calculator?
It does the arithmetic accurately for the rate you choose. GST rates and rules change, so treat results as indicative and check them against official sources. GST calculator.
What are match-making and daily prediction based on?
Both follow the Jain Jyotish nakshatra method, using Tara, Chandra Bala, rashi and planetary-lord relationships from saved birth profiles, and run on your device. Match-making gives a plain-language reading, not a percentage. They are traditional practices, not scientifically validated. Match-making.
Can I set reminders for tithis, prayers or family dates?
Yes. Personal events ring as alarms. Notes on any calendar day can repeat every year by tithi, Hijri, Roj/Mah, Nanakshahi or Jain date, with a reminder the day before. Important tithis such as Ekadashi can remind you too. Reminders.
What are cards in OIOA?
A card maker for 13 occasions, including Shok Sandesh, Shradhanjali, prayer meeting, wedding, birthday and festival cards, in 13 languages, with a photo and ready-written messages. Cards.
What are family, contacts and groups for?
A Family is a private space for relatives with shared contacts, family events and birthdays. The Family Tree records generations with tithis and remembrance dates. Groups suit societies, weddings and committees, with updates, events, posting rules and moderation. Shared contacts put a Family’s or Group’s list into members’ phone books.
Family Tree and shared contacts
What makes OIOA's Family Tree different?
It records what Indian families actually remember: a father’s name, birth, marriage and death tithis, ‘born before 1960, exact date not known’, and a traditional remembrance date. Relatives can be invited on WhatsApp and linked as themselves. Family Tree.
Can I share many contacts with my family at once?
Yes. Add contacts once to a Family or Group list. Every member who opts in gets them in their phone’s Contacts app, and edits and removals reach them on sync. Share family contacts in one go.
Will OIOA delete or change my own contacts?
No. OIOA tags every entry it creates and checks that tag before updating or removing anything, so contacts you saved yourself are never changed or deleted. If export is paused, existing entries are left as they are.
Do my relatives need OIOA to be in the Family Tree?
No. Anyone can be added as a person. Relatives who use OIOA can be invited and linked to their own person in the tree.
Do shared features work without the internet?
Yes. Changes are saved on your phone first and uploaded when you tap SYNC. If an upload is refused, the change is kept and shown to you rather than lost. OIOA-ID and sync.
Feedback and corrections
I found a wrong date or timing. What should I do?
Please tell us what we missed. Include your location, the date, what OIOA showed, what you expected and your source. We check every report.
How long does it take to hear back?
If you leave contact details and agree to a reply, we aim to respond within 15 days. Grievances under the IT Rules are acknowledged within 24 hours and resolved within 15 days. See the correction policy.
Where can I see what is being added?
On the public roadmap, which lists what is live, what is coming soon and which requests are under review.
Can I help check content for my community?
Yes, and we’d be grateful. Mention it when you send a request and leave contact details so we can reach you.
How do I report something offensive or inappropriate?
Use the grievance redressal page. We take these reports seriously and respond within the timelines stated there.
Still have a question? Contact us, or if something in the app looks wrong, tell us what we missed.