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Can I use an sqlite database created for android in IOS

I have an Android app I wrote that uses a sqllite database,(the app is used for the reservation) now I want to write the same app for iPhone and I want to use the same database I used in Android app. My question is can I use the same database in IOS.
If yes, then how can be used and where I place the sqllite database (I mean what folder)? and the users must be online to see the update in the database ?

Can I use an sqlite database created for android in IOS?
Yes, an SQLite database is a a file (or potentially 3 files if using Write-Ahead logging). It's simply a matter of copying the file(s).
Typically (i.e. if not specifying otherwise) an SQLite database is stored in data/data/your_package/database/the_database_name
where your_package is as per the App and the_database_name is the file name (may or may not have an extension).
Note if the database uses Write-ahead logging then 2 other files may exist, these being the_database_name-wal and the_database_name-shm. If they exist and are not empty, they need to also be copied.
However,
and the users must be online to see the update in the database ?
Is a completely different matter though. SQLite is not suited to a client/server situation, as you would have to write all the code to provide this functionality. See Appropriate Uses For SQLite.
Firebase may be an option if you don't mind Google's policies reqgarding information privacy. Otherwise you are likely then looking at something like MySQL/MariaDB.

Which approach is better creating database programmatically or copying it from assets folder?

Since there are two ways by which we can store or copy the data from database. one is from sqlite file which we lay in assets folder and another by database which is created programmatically.
I have following questions regarding the sqlite database in android:
1.which performs faster while getting performing select query from database and why?
2.what are the advantages of each approach.
I found on internet but i could not get any proper information, the only thing that i come to know by Googling is copying data from assets is better for static data like list of country(that is obvious because you will not perform any bulk operation of inserting data programmatcially in android). Any help regarding this is appreciated . :)

It does not make a difference.
Your select query is performed on the final database, which would be identical whether you copied it from assets, or imported it programmatically. Your approach to its creation does not influence its behaviour.
As for advantages, that's entirely up to you. In some scenarios, having a base database in assets would give you better, and easier to read, control over versioning, as you could commit it easily with your repository, vs. having thousands of SQL statements in code.
On the flip side, updating a database that you copy from the assets folder with each version could be difficult, especially if you modify data within the app frequently. Instead of programmatically simply altering the schema or data on update, you would have to export any modifications, copy the new database, and then import all your modifications by performing some form of merge.

Is there any way to extract queries from SQLite?

I'm trying to create some sort of backup & restore function in my app. Before that, I've been reading for a while to understand if it's possible to achieve, but I found out this question:
Sqlite DB Android Backup/Restore
The only other way I could see to do it, would be to read the actual contents of the DB and generate a file containing the SQL which which it can be restored from, this is obviously a more complex and doesn't offer any advantages to justify this complexity.
This answer, I think, is the best way to accomplish that; not explorting the .db file, but exporting queries.
You know; when you export a SQL data from mysql, you get a file which contains all the queries that creates the structure and queries that fill the structure with data.
That's what I'm trying to mimic; generate a file which contains sql queries from a .db file.
Do you guys think it's possible, I mean, is there any builtin method to achieve that?
Otherwise, if its too hard to handle, how do you manage to avoid what this user (https://stackoverflow.com/a/10842043/1943607) is talking about?
So, I disabled WAL with "PRAGMA journal_mode = DELETE" and then I was able to view the database in the browser and able to restore it on my test device fine.
That previous part, I can't understand it. Is this a configuration you set to sqlite?
Thanks

I haven't actually tried this with sqlite, but with mysql you could do things like create "dumps" of your database. Those dumps contained exactly what you describe: a set of queries that, when executed together, recreate the database, including the contents.
Judging from the "sqlite3" documentation found at http://www.sqlite.org/sqlite.html (especially the "Converting An Entire Database To An ASCII Text File" section), you can do the same for sqlite. Since you can execute shell commands from a java application (using Runtime.getRuntime().exec() methods), and you are the "owner" (Linux user id) of the database, you should be able to run this "sqlite3 .dump" command even on a non-rooted device. I have never seen an Android device without the sqlite3 tool installed, so the command should always be available.
Moreover, since dump file is just a text file, you should be able to prepend any PRAGMA's to it that are required for compatibility (like the one you quoted).
I haven't tested any of this, but just wanted to think with you on this interesting topic.

An sqlite database is just a file so you could copy the file but I think you may have problems with permissions in android preventing you from accessing the database.
A better solution IMO would be to sync your data to an external website.
Using a combination of a custom sync adapter and the account manager with a website or web service that has a RESTfull api to receive and send the synced data would be the most reliable approach.
http://developer.android.com/training/id-auth/identify.html is a great introduction to setting up the account manager.
And for a custom sync adapter this is a great starting point.
http://www.c99.org/2010/01/23/writing-an-android-sync-provider-part-1/
and http://www.c99.org/2010/01/23/writing-an-android-sync-provider-part-2/
And finally an explanation of how it all fits together
https://sites.google.com/site/andsamples/concept-of-syncadapter-androidcontentabstractthreadedsyncadapter
The above approach would enable a user to switch phones and retain data at the same time and the data would always be up to date (providing you sync at the appropriate times.
It seems like a lot of work as you will need to set up a web service but it is the BEST way to make sure data is kept safe and secure and can be restored and backed up at any point.
For a web service there are lots of options available to you including cloud services such as Google docs or writing your own website. Ruby on Rails is a great solution for developing your own site as you get a full RESTfull api out of the box and it;'s dead easy to secure/lock down a rails site to authorised users only with a couple of lines of code and with Heroku you can get free hosting.
As usual with Android development the simplest of requirements actually ends up being the most difficult to implement but where data safety is paramount then it's worth the effort to do it properly.

The question is too open to answer simply because the changes that may apply to the db file content are open and one can't guarantee a specific behavior .
On the positive side sqlite project is an open source and the format of the DB file is specified Here
After taking a look there, it seems very possible/not too complicated to parse any DB file looking for Data Only and write it/dump it to another functional db file.
I believe this is the fastest and cleanest solution to the issue in hand.
so to wrap up:
Copy DB file everytime you want to back it up.
When you want to restore create a new DB using Android APIs.
Parse the data from the backed up file and write them to the newly created DB.
P.S:
regarding how to use
PRAGMA journal_mode = DELETE
Simply use db.exec("PRAGMA journal_mode = DELETE"); when creating the DB

Shipping a (huge!) SQLite3 DB with Android app

I need to ship an app that uses read-only access to several preexisting SQLite3 DB's that each are a couple of 100MB's, total combines size > 1GB. The databases are created on a Mac, and are currently used in a shipping iOS app. I am pretty proficient in Java, but new to Android.
This leads to the following questions:
1) Will I need to modify the databases? I only plan to use them with SQLiteDatabase::rawQuery queries, so no nee for bindings and metadata I hope.
2) It it really correct that even if the DB's will only be used as read-only, I'll have to copy them out of the app bundle or download them to user directory on first start-up?
3) The queries can be slow. I want to run them in a thread and provide data via a callback. Is this done the way it's done in normal Java (Runnable/Thread), or will I have to use another method?
4) Is there anything else that's obvious to the Androidan that I have clearly missed?

1) No, it should work fine.
2) Yes, if you want to ship an APK that is over 50Mb you will need to use an expansion file.
3) For easy background tasks with a call back you could use an ASyncTask.

for a decent example of a sqlite helper class look here
you shouldnt need to edit the database. my sqlite databases work the same wether I access them via sqlite3 or with the android my sqlite helper class
once you copy them you can read and write
not really sure about this answer. i will say though that the database helper class above seems to work just fine (fast) but my db is smaller (500kb)
dont think so

Is XML a good way to organize App data and keep it up to date on the Market?

this should be an easy one for whoever published Android Apps before...
Here is my situation:
I'm trying to develop a "city guide" app and I was wondering if my idea of working with .XML files to structure my data (the client provided a .PDF file with pictures, address, tel. no, websites, opening hours of the different destinations) is the best way to go.
I was hoping to be able to write this app as an "interpreter" for this type of .XML and then easily include other cities or destinations in a city by updating that input XML file.
So this is not a technical question, I know how to pull this off, the question is if this is a good way to go? How do you keep an app easily up to date? Would a altered XML trigger a Market wide update notification ?
My research lead me to believe that this is a comfortable way to update a published Android Market app (prior to this inquiry I consulted:
http://developer.android.com/guide/publishing/publishing.html
All helpful hints and suggestions will be greatly appreciated.
Regards,
Veo.

Once I developed such kind of an app that had to contain the whole information in itself. I structured it in SQLite database that I was shipping along with the application. The file was not directly readable (or at least easy to read) from the assets folder, but every time when the file was altered I copied the sqlite file to the application storage and used it as ordinary application database. The cool thing is that this way I did not have to pay for the parsing of xml every time the application ran.
Several notes here:
My database grew too big and I had to split it in files of 1MB, because this is the limit for a file in the asset folder. For more info see here:
The database update mechanism with the database version still worked well.
When you create the database manually you need to take into account that Android expects one system table to exist in it (it is automatically created if the database is created in Android code). Basically see this answer here for more info on that.